diff --git a/OpenChange/MAPIStoreMailContext.m b/OpenChange/MAPIStoreMailContext.m
index 7ec79ad50..c1f39565f 100644
--- a/OpenChange/MAPIStoreMailContext.m
+++ b/OpenChange/MAPIStoreMailContext.m
@@ -160,23 +160,25 @@ MakeDisplayFolderName (NSString *folderName)
   for (count = 0; count < max; count++)
     {
       context = talloc_zero (memCtx, struct mapistore_contexts_list);
-      // secondaryFolders has the names (1) Imap4Encoded and (2) asCSSIdentifier
-      //     e.g.: Probl&AOg-mes_SP_de_SP_synchronisation
+      // secondaryFolders has the names (1) Imap4Encoded ,(2) asCSSIdentifier and (3) "folder"-prefixed
+      //     e.g.: folderProbl&AOg-mes_SP_de_SP_synchronisation
       currentName = [secondaryFolders objectAtIndex: count];
-      // To get the real name we have to revert that (applying the decode functions)
-      // in reverse order
+      // To get the real name we have to revert that (applying the decode functions
+      // in reverse order)
       //     e.g.: Problèmes de synchronisation
-      realName = [[currentName fromCSSIdentifier]
-                               stringByDecodingImap4FolderName];
+      realName = [[[currentName substringFromIndex: 6]
+                                fromCSSIdentifier]
+                                stringByDecodingImap4FolderName];
       // And finally to represent that as URI we have to (1) asCSSIdentifier,
-      // (2) Imap4Encode and (3) AddPercentEscapes
-      //     e.g.: Probl&AOg-mes_SP_de_SP_synchronisation
+      // (2) Imap4Encode (3) AddPercentEscapes and (4) add the "folder" prefix
+      //     e.g.: folderProbl&AOg-mes_SP_de_SP_synchronisation
       // In the example there are no percent escapes added because is already ok
       stringData = [[[realName asCSSIdentifier]
                                stringByEncodingImap4FolderName]
                                stringByAddingPercentEscapesUsingEncoding: NSUTF8StringEncoding];
+      stringData = [NSString stringWithFormat: @"folder%@", stringData];
       context->url = [[NSString stringWithFormat: @"%@%@", urlBase, stringData] asUnicodeInMemCtx: context];
-      context->name = [[realName substringFromIndex: 6] asUnicodeInMemCtx: context];
+      context->name = [realName asUnicodeInMemCtx: context];
       context->main_folder = false;
       context->role = MAPISTORE_MAIL_ROLE;
       context->tag = "tag";
@@ -200,7 +202,7 @@ MakeDisplayFolderName (NSString *folderName)
                                                andTDBIndexing: NULL];
   accountFolder = [[userContext rootFolders] objectForKey: @"mail"];
   folderName = [NSString stringWithFormat: @"folder%@",
-                         [newFolderName asCSSIdentifier]];
+                         [[newFolderName stringByEncodingImap4FolderName] asCSSIdentifier]];
   newFolder = [SOGoMailFolder objectWithName: folderName
                                  inContainer: accountFolder];
   if ([newFolder create])
@@ -209,7 +211,7 @@ MakeDisplayFolderName (NSString *folderName)
                                        withString: @"%40"],
                              [userName stringByReplacingOccurrencesOfString: @"@"
                                        withString: @"%40"],
-                             [[folderName stringByEncodingImap4FolderName] stringByAddingPercentEscapesUsingEncoding: NSUTF8StringEncoding]];
+                             [folderName stringByAddingPercentEscapesUsingEncoding: NSUTF8StringEncoding]];
   else
     mapistoreURI = nil;
 
diff --git a/Scripts/openchange_user_cleanup b/Scripts/openchange_user_cleanup
index e67289480..93a91c8ea 100755
--- a/Scripts/openchange_user_cleanup
+++ b/Scripts/openchange_user_cleanup
@@ -268,6 +268,9 @@ def asCSSIdentifier(inputString):
 
     newChars = []
 
+    if str.isdigit(inputString[0]):
+        newChars.append("_")
+
     for c in inputString:
         if c in cssEscapingCharMap:
             newChars.append(cssEscapingCharMap[c])
diff --git a/SoObjects/Mailer/SOGoMailAccount.m b/SoObjects/Mailer/SOGoMailAccount.m
index 97057a1c4..f24af644d 100644
--- a/SoObjects/Mailer/SOGoMailAccount.m
+++ b/SoObjects/Mailer/SOGoMailAccount.m
@@ -206,8 +206,8 @@ static NSString *inboxFolderName = @"INBOX";
         [folders removeObjectsInArray: nss];
     }
 
-  return [[folders stringsWithFormat: @"folder%@"]
-           resultsOfSelector: @selector (asCSSIdentifier)];
+  return [[folders resultsOfSelector: @selector (asCSSIdentifier)]
+           stringsWithFormat: @"folder%@"];
 }
 
 - (NSArray *) toManyRelationshipKeys
diff --git a/SoObjects/Mailer/SOGoMailFolder.m b/SoObjects/Mailer/SOGoMailFolder.m
index 671a6caf6..884e838b6 100644
--- a/SoObjects/Mailer/SOGoMailFolder.m
+++ b/SoObjects/Mailer/SOGoMailFolder.m
@@ -197,9 +197,9 @@ _compareFetchResultsByMODSEQ (id entry1, id entry2, void *data)
 {
   NSArray *subfolders;
 
-  subfolders = [[self subfolders] stringsWithFormat: @"folder%@"];
+  subfolders = [[self subfolders] resultsOfSelector: @selector (asCSSIdentifier)];
 
-  return [subfolders resultsOfSelector: @selector (asCSSIdentifier)];
+  return [subfolders stringsWithFormat: @"folder%@"];
 }
 
 - (NSArray *) subfolders
@@ -632,7 +632,7 @@ _compareFetchResultsByMODSEQ (id entry1, id entry2, void *data)
 		inContext: (id) localContext
 {
   NSArray *folders;
-  NSString *currentFolderName, *currentAccountName;
+  NSString *currentFolderName, *currentAccountName, *destinationAccountName;
   NSMutableString *imapDestinationFolder;
   NGImap4Client *client;
   id result;
@@ -640,24 +640,24 @@ _compareFetchResultsByMODSEQ (id entry1, id entry2, void *data)
 
 #warning this code will fail on implementation using something else than '/' as delimiter
   imapDestinationFolder = [NSMutableString string];
-  folders = [[destinationFolder componentsSeparatedByString: @"/"]
-              resultsOfSelector: @selector (fromCSSIdentifier)];
+  folders = [destinationFolder componentsSeparatedByString: @"/"];
   max = [folders count];
   if (max > 1)
     {
       currentAccountName = [[self mailAccountFolder] nameInContainer];
       client = [[self imap4Connection] client];
       [imap4 selectFolder: [self imap4URL]];
+      destinationAccountName = [[folders objectAtIndex: 1] fromCSSIdentifier];
 
       for (count = 2; count < max; count++)
         {
-          currentFolderName = [[folders objectAtIndex: count] substringFromIndex: 6];
+          currentFolderName = [[[folders objectAtIndex: count] substringFromIndex: 6] fromCSSIdentifier];
           [imapDestinationFolder appendFormat: @"/%@", currentFolderName];
         }
 
       if (client)
         {
-          if ([[folders objectAtIndex: 1] isEqualToString: currentAccountName])
+          if ([destinationAccountName isEqualToString: currentAccountName])
             {
               // We make sure the destination IMAP folder exist, if not, we create it.
               result = [[client status: imapDestinationFolder
@@ -686,7 +686,7 @@ _compareFetchResultsByMODSEQ (id entry1, id entry2, void *data)
               
               userFolder = [[context activeUser] homeFolderInContext: context];
               accounts = [userFolder lookupName: @"Mail"  inContext: context  acquire: NO];
-              account = [accounts lookupName: [folders objectAtIndex: 1] inContext: localContext acquire: NO];
+              account = [accounts lookupName: destinationAccountName inContext: localContext acquire: NO];
 
               if ([account isKindOfClass: [NSException class]])
                 {
diff --git a/UI/MailerUI/UIxMailFolderActions.m b/UI/MailerUI/UIxMailFolderActions.m
index 4515eac4f..80fd4fa20 100644
--- a/UI/MailerUI/UIxMailFolderActions.m
+++ b/UI/MailerUI/UIxMailFolderActions.m
@@ -106,7 +106,7 @@
   keyForMsgUIDs = [NSString stringWithFormat:@"/%@/%@", currentAccount, currentMailbox];
 
   newFolderName = [[context request] formValueForKey: @"name"];
-  newKeyForMsgUIDs = [[NSString stringWithFormat:@"/%@/folder%@", currentAccount, newFolderName] asCSSIdentifier];
+  newKeyForMsgUIDs = [NSString stringWithFormat:@"/%@/folder%@", [currentAccount asCSSIdentifier], [newFolderName asCSSIdentifier]];
   error = [co renameTo: newFolderName];
   if (error)
     {
diff --git a/UI/MailerUI/UIxMailMainFrame.m b/UI/MailerUI/UIxMailMainFrame.m
index 488449207..e6ee428e5 100644
--- a/UI/MailerUI/UIxMailMainFrame.m
+++ b/UI/MailerUI/UIxMailMainFrame.m
@@ -688,8 +688,8 @@
 
 		  for (k = 0; k < [pathComponents count]; k++)
 		    {
-                      component = [NSString stringWithFormat: @"folder%@", [pathComponents objectAtIndex: k]];
-                      [path appendString: [component asCSSIdentifier]];
+                      component = [[pathComponents objectAtIndex: k] asCSSIdentifier];
+                      [path appendString: [NSString stringWithFormat: @"folder%@", component]];
 		      if (k < [pathComponents count] - 1)
 			[path appendString: @"/"];
 		    }
diff --git a/UI/WebServerResources/MailerUI.js b/UI/WebServerResources/MailerUI.js
index 9144db5b9..d42e94c9c 100644
--- a/UI/WebServerResources/MailerUI.js
+++ b/UI/WebServerResources/MailerUI.js
@@ -3029,7 +3029,7 @@ Mailbox.prototype = {
 
         var currentFolder = this;
         while (currentFolder.parentFolder) {
-            fullName = ("/folder" + currentFolder.name).asCSSIdentifier() + fullName;
+            fullName = "/folder" + currentFolder.name.asCSSIdentifier() + fullName;
             currentFolder = currentFolder.parentFolder;
         }