diff --git a/admin/inst_module.php b/admin/inst_module.php
index 2309292be..d461956d1 100644
--- a/admin/inst_module.php
+++ b/admin/inst_module.php
@@ -214,8 +214,8 @@ function company_extensions($id)
 		{
 			if (check_value('Active'.$i) && !check_src_ext_version($ext['version']))
 			{
-				display_warning(sprintf(_("Package '%s' is incompatible with current application version and cannot be activated.\n")
-					. _("Check Install/Activate page for newer package version."), $ext['name']));
+				display_warning(sprintf(_("Package '%s' version '%s' is incompatible with current application version and cannot be activated.\n")
+					. _("Check Install/Activate page for newer package version."), $ext['name'], $ext['version']));
 				continue;
 			}
 			$activated = activate_hooks($ext['package'], $comp, !$ext['active']);	// change active state
diff --git a/includes/packages.inc b/includes/packages.inc
index 99b620d30..8be885389 100644
--- a/includes/packages.inc
+++ b/includes/packages.inc
@@ -733,6 +733,10 @@ function check_src_ext_version($ext_v)
 	$app = explode('.', substr($src_version, 0, strspn($src_version, "0123456789.")));
 	$pkg = explode('.', substr($ext_v, 0, strspn($ext_v, "0123456789.")));
 
+	if ($ext_v == '' || $ext_v == '-') {
+		return true;
+	}
+
 	for ($i=0; $i < min($compat_levels, count($app)); $i++)
 		if ($pkg[$i] < $app[$i])
 			return false;