Comment 7 for bug 137514

I can confirm this. I've been using sshfs since around Breezy and am how using Gutsy and Hardy, and in every version I've had this problem, although I have the impression it's become more consistent since Gutsy. Here are some observations I've made:

1. sshfs locks up consistently (no exceptions) whenever left idle for over maybe 20 or 30 minutes, regardless of what host I'm connected to and what kind of network connection I use (wireless, t1, cable).
2. Any program (terminal, nautilus, media player, etc.) that tries to access an sshfs file/directory locks up (sometimes uninterruptibly).
3. The only way to unlock these programs is to kill the ssh process (ssh -x -a -oClearAllForwardings=yes -2 remotehost.org -s sftp). I used to lazy unmount ("fusermount -uz mountpoint"), which frees up the mount point but leaves the ssh and other processes hanging.

I'll have to try to see if it still happens without network-manager--it may be that I started having this problem when I started using NM.

I think this is a major problem that makes sshfs practically unusable for anyone who doesn't like to constantly kill and restart processes through the command line.