diff --git a/modules/imap/hm-jmap.php b/modules/imap/hm-jmap.php
index 62440e5679..440be0451c 100644
--- a/modules/imap/hm-jmap.php
+++ b/modules/imap/hm-jmap.php
@@ -9,12 +9,14 @@
 /**
  * public interface to JMAP commands
  * @subpackage imap/lib
- */ 
-class Hm_JMAP {
+ */
+class Hm_JMAP extends Hm_JMAP_Email {
 
     private $api;
     private $session;
     private $api_url;
+    private $download_url;
+    private $upload_url;
     private $account_id;
     private $headers;
     private $delim = '.';
@@ -22,6 +24,11 @@ class Hm_JMAP {
     private $requests = array();
     private $responses = array();
     private $folder_list = array();
+    private $streaming_msg = '';
+    private $msg_part_id = 0;
+    private $append_mailbox = false;
+    private $append_seen = false;
+    private $append_result = false;
     private $sorts = array(
         'ARRIVAL' => 'receivedAt',
         'FROM' => 'from',
@@ -49,33 +56,139 @@ class Hm_JMAP {
     /** 
      * PUBLIC INTERFACE
      */
-        
+
     public function __construct() {
         $this->api = new Hm_API_Curl();
     }
-    
-    public function create_mailbox($mailbox) {
+
+    public function get_mailbox_status($mailbox, $args=array('UNSEEN', 'UIDVALIDITY', 'UIDNEXT', 'MESSAGES', 'RECENT')) {
     }
 
-    public function delete_mailbox($mailbox) {
+    public function append_start($mailbox, $size, $seen=true) {
+        $this->append_mailbox = $mailbox;
+        $this->append_seen = $seen;
+        return true;
     }
 
-    public function start_message_stream($uid, $message_part) {
+    public function append_feed($string) {
+        $upload_url = str_replace('{accountId}', $this->account_id, $this->upload_url);
+        $res = $this->send_command($upload_url, array(), 'POST', $string, array(2 => 'Content-Type: multipart/form-data'));
+        if (!is_array($res) || !array_key_exists('blobId', $res)) {
+            return false;
+        }
+        $blob_id = $res['blobId'];
+        $methods = array(array(
+            'Email/import',
+            array(
+                'accountId' => $this->account_id,
+                'emails' => array(1 => array(
+                    'mailboxIds' => array($this->folder_name_to_id($this->append_mailbox) => true),
+                    'blobId' => $blob_id
+                ))
+            ),
+            'af'
+        ));
+        /* TODO: figure out blobId issue */
     }
 
-    public function read_stream_line($size=1024) {
+    public function append_end() {
+        $res = $this->append_result;
+        $this->append_result = false;
+        $this->append_mailbox = false;
+        $this->append_seen = false;
+        return $res;
     }
 
-    public function append_start($mailbox, $size, $seen=true) {
+    public function start_message_stream($uid, $message_part) {
+
+        $struct = $this->get_message_structure($uid);
+        $part_struct = $this->search_bodystructure($struct, array('imap_part_number' => $message_part));
+        $blob_id = false;
+        $name = false;
+        $type = false;
+        if (is_array($part_struct) && array_key_exists($message_part, $part_struct)) {
+            if (array_key_exists('blob_id', $part_struct[$message_part])) {
+                $blob_id = $part_struct[$message_part]['blob_id'];
+            }
+            if (array_key_exists('name', $part_struct[$message_part])) {
+                $name = $part_struct[$message_part]['name'];
+            }
+            else {
+                $name = sprintf('message_%s', $message_part);
+            }
+            if (array_key_exists('type', $part_struct[$message_part])) {
+                $type = $part_struct[$message_part]['type'];
+            }
+        }
+        if (!$name || !$blob_id || !$type) {
+            return 0;
+        }
+        $download_url = str_replace(
+            array('{accountId}', '{blobId}', '{name}', '{type}'),
+            array(
+                urlencode($this->account_id),
+                urlencode($blob_id),
+                urlencode($name),
+                urlencode('application/octet-stream')
+            ),
+            $this->download_url
+        );
+        $this->api->format = 'binary';
+        $this->streaming_msg = $this->send_command($download_url, array(), 'GET');
+        $this->api->format = 'json';
+        return strlen($this->streaming_msg);
     }
 
-    public function append_feed($string) {
+    public function read_stream_line($size=1024) {
+        $res = $this->streaming_msg;
+        $this->streaming_msg = false;
+        return $res;
     }
 
-    public function append_end() {
+    public function create_mailbox($mailbox) {
+        list($name, $parent) = $this->split_name_and_parent($mailbox);
+        $methods = array(array(
+            'Mailbox/set',
+            array(
+                'accountId' => $this->account_id,
+                'create' => array(NULL => array('parentId' => $parent, 'name' => $name))
+            ),
+            'cm'
+        ));
+        $created = $this->send_and_parse($methods, array(0, 1, 'created'), array());
+        $this->reset_folders();
+        return $created && count($created) > 0;
     }
 
-    public function get_mailbox_status($mailbox, $args=array('UNSEEN', 'UIDVALIDITY', 'UIDNEXT', 'MESSAGES', 'RECENT')) {
+    public function delete_mailbox($mailbox) {
+        $ids = array($this->folder_name_to_id($mailbox));
+        $methods = array(array(
+            'Mailbox/set',
+            array(
+                'accountId' => $this->account_id,
+                'destroy' => $ids
+            ),
+            'dm'
+        ));
+        $destroyed = $this->send_and_parse($methods, array(0, 1, 'destroyed'), array());
+        $this->reset_folders();
+        return $destroyed && count($destroyed) > 0;
+    }
+
+    public function rename_mailbox($mailbox, $new_mailbox) {
+        $id = $this->folder_name_to_id($mailbox);
+        list($name, $parent) = $this->split_name_and_parent($new_mailbox);
+        $methods = array(array(
+            'Mailbox/set',
+            array(
+                'accountId' => $this->account_id,
+                'update' => array($id => array('parentId' => $parent, 'name' => $name))
+            ),
+            'rm'
+        ));
+        $updated = $this->send_and_parse($methods, array(0, 1, 'updated'), array());
+        $this->reset_folders();
+        return $updated && count($updated) > 0;
     }
 
     public function get_state() {
@@ -103,15 +216,7 @@ public function get_first_message_part($uid, $type, $subtype=false, $struct=fals
 
         $subset = array_slice(array_keys($matches), 0, 1);
         $msg_part_num = $subset[0];
-        $struct = array_slice($matches, 0, 1);
-
-        if (isset($struct[$msg_part_num])) {
-            $struct = $struct[$msg_part_num];
-        }
-        elseif (isset($struct[0])) {
-            $struct = $struct[0];
-        }
-        return array($msg_part_num, $this->get_message_content($uid, $msg_part_num, false, $struct));
+        return array($msg_part_num, $this->get_message_content($uid, $msg_part_num));
     }
 
     public function get_mailbox_page($mailbox, $sort, $rev, $filter, $offset=0, $limit=0, $keyword=false) {
@@ -134,7 +239,7 @@ public function get_mailbox_page($mailbox, $sort, $rev, $filter, $offset=0, $lim
                     'limit' => $limit,
                     'calculateTotal' => true
                 ),
-                'gmp' 
+                'gmp'
             )
         );
         $res = $this->send_command($this->api_url, $methods);
@@ -149,7 +254,7 @@ public function get_folder_list_by_level($level=false) {
             $level = '';
         }
         if (count($this->folder_list) == 0) {
-            $this->folder_list = $this->parse_imap_folders($this->get_folder_list());
+            $this->reset_folders();
         }
         return $this->parse_folder_list_by_level($level);
     }
@@ -240,10 +345,9 @@ public function get_message_list($uids) {
                 'properties' => $flds,
                 'bodyProperties' => $body
             ),
-            'gml' 
+            'gml'
         ));
-        $res = $this->send_command($this->api_url, $methods);
-        foreach ($this->search_response($res, array(0, 1, 'list'), array()) as $msg) {
+        foreach ($this->send_and_parse($methods, array(0, 1, 'list'), array()) as $msg) {
             $result[] = $this->normalize_headers($msg);
         }
         return $result;
@@ -255,7 +359,7 @@ public function get_message_structure($uid) {
         return $converted;
     }
 
-    public function get_message_content($uid, $message_part, $max=false, $struct=true) {
+    public function get_message_content($uid, $message_part, $max=false, $struct=false) {
         $methods = array(array(
             'Email/get',
             array(
@@ -264,10 +368,9 @@ public function get_message_content($uid, $message_part, $max=false, $struct=tru
                 'fetchAllBodyValues' => true,
                 'properties' => array('bodyValues')
             ),
-            'gmc' 
+            'gmc'
         ));
-        $res = $this->send_command($this->api_url, $methods);
-        return $this->search_response($res, array(0, 1, 'list', 0, 'bodyValues', $message_part, 'value'));
+        return $this->send_and_parse($methods, array(0, 1, 'list', 0, 'bodyValues', $message_part, 'value'));
     }
 
     public function search($target='ALL', $uids=false, $terms=array(), $esearch=array(), $exclude_deleted=true, $exclude_auto_bcc=true, $only_auto_bcc=false) {
@@ -293,8 +396,7 @@ public function search($target='ALL', $uids=false, $terms=array(), $esearch=arra
                 's'
             )
         );
-        $res = $this->send_command($this->api_url, $methods);
-        return $this->search_response($res, array(0, 1, 'ids'), array());
+        return $this->send_and_parse($methods, array(0, 1, 'ids'), array());
     }
 
     public function get_message_headers($uid, $message_part=false, $raw=false) {
@@ -308,39 +410,12 @@ public function get_message_headers($uid, $message_part=false, $raw=false) {
                 'properties' => $flds,
                 'bodyProperties' => array()
             ),
-            'gmh' 
+            'gmh'
         ));
-        $res = $this->send_command($this->api_url, $methods);
-        $headers = $this->search_response($res, array(0, 1, 'list', 0), array());
+        $headers = $this->send_and_parse($methods, array(0, 1, 'list', 0), array());
         return $this->normalize_headers($headers);
     }
 
-    public function rename_mailbox($mailbox, $new_mailbox) {
-        $id = $this->folder_name_to_id($mailbox);
-        $parent = explode($this->delim, $new_mailbox);
-        $name = array_pop($parent);
-        $parent = implode($this->delim, $parent);
-        if (!$parent) {
-            $parent = NULL;
-        }
-        else {
-            $parent = $this->folder_name_to_id($parent);
-        }
-        $methods = array(array(
-            'Mailbox/set',
-            array(
-                'accountId' => $this->account_id,
-                'update' => array($id => array('parentId' => $parent, 'name' => $name))
-            ),
-            'ma' 
-        ));
-        $res = $this->send_command($this->api_url, $methods);
-        $updated = $this->search_response($res, array(0, 1, 'updated')); 
-        /* TODO: Bust folder list cache */
-        //$this->folder_list = $this->parse_imap_folders($this->get_folder_list());
-        return count($updated) > 0;
-    } 
-
     public function message_action($action, $uids, $mailbox=false, $keyword=false) {
         $methods = array();
         $key =false;
@@ -359,8 +434,7 @@ public function message_action($action, $uids, $mailbox=false, $keyword=false) {
         if (!$key) {
             return false;
         }
-        $res = $this->send_command($this->api_url, $methods);
-        $changed_uids = array_keys($this->search_response($res, array(0, 1, $key)));
+        $changed_uids = array_keys($this->send_and_parse($methods, array(0, 1, $key), array()));
         return count($changed_uids) == count($uids);
     }
 
@@ -376,7 +450,7 @@ public function search_bodystructure($struct, $search_flds, $all=true, $res=arra
 
     private function move_copy_methods($action, $uids, $mailbox) {
         /* TODO: this assumes a message can only be in ONE mailbox, other refs will be lost,
-            * we should switch to "patch to fix this */
+                 we should switch to "patch" syntax to fix this */
         if ($action == 'MOVE') {
             $mailbox_ids = array('mailboxIds' => array($this->folder_name_to_id($mailbox) => true));
         }
@@ -395,7 +469,7 @@ private function move_copy_methods($action, $uids, $mailbox) {
                 'accountId' => $this->account_id,
                 'update' => $keywords
             ),
-            'ma' 
+            'ma'
         ));
     }
 
@@ -411,7 +485,7 @@ private function modify_msg_methods($action, $uids) {
                 'accountId' => $this->account_id,
                 'update' => $keywords
             ),
-            'ma' 
+            'ma'
         ));
     }
 
@@ -422,7 +496,7 @@ private function delete_msg_methods($uids) {
                 'accountId' => $this->account_id,
                 'destroy' => $uids
             ),
-            'ma' 
+            'ma'
         ));
     }
 
@@ -434,7 +508,7 @@ private function get_raw_bodystructure($uid) {
                 'ids' => array($uid),
                 'properties' => array('bodyStructure')
             ),
-            'gbs' 
+            'gbs'
         ));
         $res = $this->send_command($this->api_url, $methods);
         return $this->search_response($res, array(0, 1, 'list', 0, 'bodyStructure'), array());
@@ -450,13 +524,19 @@ private function parse_bodystructure_response($data) {
         }
         return array($top);
     }
-    
+
     private function parse_subs($data) {
         $res = array();
         foreach ($data as $sub) {
+            if ($sub['partId']) {
+                $this->msg_part_id = $sub['partId'];
+            }
+            else {
+                $sub['partId'] = $this->msg_part_id + 1;
+            }
             $res[$sub['partId']] = $this->translate_struct_keys($sub);
             if (array_key_exists('subParts', $sub)) {
-                $res['subs'] = $this->parse_subs($sub['subParts']);
+                $res[$sub['partId']]['subs'] = $this->parse_subs($sub['subParts']);
             }
         }
         return $res;
@@ -465,7 +545,9 @@ private function parse_subs($data) {
     private function translate_struct_keys($part) {
         return array(
             'type' => explode('/', $part['type'])[0],
+            'name' => $part['name'],
             'subtype' => explode('/', $part['type'])[1],
+            'blob_id' => array_key_exists('blobId', $part) ? $part['blobId'] : false,
             'size' => $part['size'],
             'attributes' => array('charset' => $part['charset'])
         );
@@ -501,8 +583,20 @@ private function init_session($data, $url, $port) {
             $port,
             $data['apiUrl']
         );
+        $this->download_url = sprintf(
+            '%s:%s%s',
+            preg_replace("/\/$/", '', $url),
+            $port,
+            $data['downloadUrl']
+        );
+        $this->upload_url = sprintf(
+            '%s:%s%s',
+            preg_replace("/\/$/", '', $url),
+            $port,
+            $data['uploadUrl']
+        );
         $this->account_id = array_keys($data['accounts'])[0];
-        $this->folder_list = $this->parse_imap_folders($this->get_folder_list());
+        $this->reset_folders();
     }
 
     private function keywords_to_flags($keywords) {
@@ -526,15 +620,41 @@ private function combine_addresses($addrs) {
         }
         return implode(', ', $res);
     }
-    private function send_command($url, $methods=array(), $method='POST', $post=array()) {
+    private function merge_headers($headers) {
+        $req_headers = $this->headers;
+        foreach ($headers as $index => $val) {
+            $req_headers[$index] = $val;
+        }
+        return $req_headers;
+    }
+
+    private function send_command($url, $methods=array(), $method='POST', $post=array(), $headers=array()) {
         $body = '';
         if (count($methods) > 0) {
             $body = $this->format_request($methods);
         }
-        $this->requests[] = array($url, $this->headers, $body, $method, $post);
-        $res = $this->api->command($url, $this->headers, $post, $body, $method);
+        $headers = $this->merge_headers($headers);
+        $this->requests[] = array($url, $headers, $body, $method, $post);
+        return $this->api->command($url, $headers, $post, $body, $method);
+    }
+
+    private function search_response($data, $key_path, $default=false) {
+        array_unshift($key_path, 'methodResponses');
+        foreach ($key_path as $key) {
+            if (is_array($data) && array_key_exists($key, $data)) {
+                $data = $data[$key];
+            }
+            else {
+                return $default;
+            }
+        }
+        return $data;
+    }
+
+    private function send_and_parse($methods, $key_path, $default=false, $method='POST', $post=array()) {
+        $res = $this->send_command($this->api_url, $methods, $method, $post);
         $this->responses[] = $res;
-        return $res;
+        return $this->search_response($res, $key_path, $default);
     }
 
     private function format_request($methods, $caps=array()) {
@@ -561,19 +681,6 @@ private function prep_url($url, $port) {
         return sprintf('%s:%s/.well-known/jmap/', $url, $port);
     }
 
-    private function search_response($data, $key_path, $default=false) {
-        array_unshift($key_path, 'methodResponses');
-        foreach ($key_path as $key) {
-            if (is_array($data) && array_key_exists($key, $data)) {
-                $data = $data[$key];
-            }
-            else {
-                return $default;
-            }
-        }
-        return $data;
-    }
-
     private function setup_selected_mailbox($mailbox, $total) {
         $this->selected_mailbox = array('detail' => array(
             'selected' => 1,
@@ -648,8 +755,8 @@ private function get_parent_recursive($vals, $lookup, $parents) {
     }
 
     private function folder_name_to_id($name) {
-        if (count($this->folder_list) == 0) {
-            $this->folder_list = $this->parse_imap_folders($this->get_folder_list());
+        if (count($this->folder_list) == 0 || !array_key_exists($name, $this->folder_list)) {
+            $this->reset_folders();
         }
         if (array_key_exists($name, $this->folder_list)) {
             return $this->folder_list[$name]['id'];
@@ -657,6 +764,10 @@ private function folder_name_to_id($name) {
         return false;
     }
 
+    private function reset_folders() {
+        $this->folder_list = $this->parse_imap_folders($this->get_folder_list());
+    }
+
     private function process_imap_search_terms($terms) {
         $converted_terms = array();
         $map = array(
@@ -677,4 +788,14 @@ private function process_imap_search_terms($terms) {
         }
         return count($converted_terms) > 0 ? $converted_terms : false;
     }
+
+    private function split_name_and_parent($mailbox) {
+        $parent = NULL;
+        $parts = explode($this->delim, $mailbox);
+        $name = array_pop($parts);
+        if (count($parts) > 0) {
+            $parent = $this->folder_name_to_id(implode($this->delim, $parts));
+        }
+        return array($name, $parent);
+    }
 }