I realize this is an old post, but in case someone is still looking for a solution to remove the duplicate samba share entries in the filebrowser, the solution is simple: Add a forward-slash after the share name in fstab:
'found this solution here: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=663140Code://server/share/ /home/john/server/share cifs [...] # here--------^
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