This was recently reported in launchpad at:
Steps to reproduce:
$ net usershare add "My Shared Folder" "/home/user/My Shared Folder"
$ net usershare list
my shared folder
If you have any questions please let me know.
Created attachment 5552 [details]
Patch the has gone into master for 3.6.0
Fix in master for 3.6.0. I don't intend to back port this fix to 3.5.x as it depends on a version upgrade in the share_info.tdb share security database.
Closing out bug report as it will be fixed in Samba 3.6.0 and higher.