diff --git a/oioswift/common/middleware/slo.py b/oioswift/common/middleware/slo.py
index 06acf3f..9464482 100644
--- a/oioswift/common/middleware/slo.py
+++ b/oioswift/common/middleware/slo.py
@@ -25,6 +25,7 @@
 from hashlib import md5
 import mimetypes
 import six
+from six.moves.urllib.parse import urlencode
 import time
 
 from oio.common.json import json
@@ -447,11 +448,14 @@ def resp_iter(total_size=total_size):
             last_yield_time = time.time()
 
             # BEGIN: New OpenIO code
+            params = {
+                'format': 'json',
+                'prefix': seg_prefix,
+                'limit': self.max_manifest_segments
+            }
             sub_req = make_subrequest(
                 req.environ,
-                path='%s?format=json&prefix=%s&limit=%d' %
-                     (segments_container_path, seg_prefix,
-                      self.max_manifest_segments),
+                path='%s?%s' % (segments_container_path, urlencode(params)),
                 method='GET',
                 headers={'x-auth-token': req.headers.get('x-auth-token')},
                 agent='%(orig)s SLO MultipartPUT', swift_source='SLO')
diff --git a/tests/functional/s3-mpu.py b/tests/functional/s3-mpu.py
index 18f5e9f..5b843f9 100755
--- a/tests/functional/s3-mpu.py
+++ b/tests/functional/s3-mpu.py
@@ -8,7 +8,7 @@
 import json
 import os
 
-ENDPOINT = os.getenv("USE_ENDPOINT", "http://127.0.0.1:5000")
+ENDPOINT = os.getenv("USE_ENDPOINT", "http://localhost:5000")
 AWS = ["aws", "--endpoint", ENDPOINT]
 
 random_chars = string.lowercase + string.digits
@@ -142,9 +142,19 @@ def run_test(bucket, path):
 
 def main():
     run_test(random_str(10),
-             "docker/registry/v2/repositories/hello/_uploads/333633b0-503f-4b2a-9b43-e56ec6445ef3/data")  # noqa
+             "docker/registry/v2/repositories/hello/_uploads/"
+             "333633b0-503f-4b2a-9b43-e56ec6445ef3/data")
+    run_test(random_str(10),
+             "docker/registry/v2/repositories/hello+world/_uploads/"
+             "333633b0-503f-4b2a-9b43-e56ec6445ef3/data")
+    run_test(random_str(10),
+             "docker/registry/v2/repositories/hello/_uploads/"
+             "333633b0-503f-4b2a-9b43-e56ec6445ef3/data+")
     run_test(random_str(10),
              "CBB_DESKTOP-1LC5CCV/C:/Bombay/Logs/titi:/12121212/titi")
+    run_test(random_str(10),
+             "CBB_DESKTOP-1LC5CCV/C:/Bombay/Logs/titi+rominet:/12121212/"
+             "titi+rominet")
     run_test(random_str(10), random_str(10))