Comment 12 for bug 207072

Acquiring a kerberos ticket from an AD server, using pam_winbind at login (or using kinit in a shell), allows a user to browse samba shares with its cached credentials.
This is described here:
https://help.ubuntu.com/community/ActiveDirectoryWinbindHowto#head-a1da1a136c89873cbd7c7a1e1fbd75d621d18c9a

Maybe gvfs expects to find this or other authentications, but in any case this behaviour is different from what happened with gnomevfs in previous releases. Users should be aware of this.
I still think that a gvfs patch is needed to ask for a password when it is required, indipendently of kerberos tickets.