Judging by the duplicate report (bug 67918) and its backtrace (http://librarian.launchpad.net/4938120/_usr_lib_gamin_gam_server.1012.crash) this is not necessarily NFS related.
-- Crash when umounting an NFS share https://launchpad.net/bugs/63476 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
