Wishing all the known and unknown Zimbra users a very haapy and propserouse new year.

I have a query regarding the folder IDs allocated by Zimbra for default folders.For default folders IDs are of the type Integer for e.g
7-Contacts folder
13-Emailed contacts folder.

Does Zimbra Client have any restriction on the type and size of newly created folders like(created inside inbox etc).?

Can I use any type as a folder ID apart from Integer? e.g Folder id of the Type Hexadecimal.

Any help or pointers on this issue will be highly useful for Zimbra Client usage.

Please provide any help on this query.

Thanking in Advance.