Nautilus file copy unreliable over SSH connections (hangs)

[Jure Sah]

While copying a large amount of files between two Ubuntu 12.04 machines using a SSH connection, when left unattended, the transfer stops after some time (an hour or so), the transfers cannot be canceled, the network share cannot be unmounted (get timeout errors, but the share remains mounted) until I restart the machine where the file transfers were innitiated in the GUI.

What I expected to happen:
1. I mount a remote folder over SSH in Nautilus
2. I innitiate a file move to a local harddisk
3. I leave the machine unattended until the transfer completes
4. The move completes or at least a useful error message is displayed and I can resume the download

What happened:
1. I mount a remote folder over SSH in Nautilus
2. I innitiate a file move to a local harddisk
3. I leave the machine unattended until the transfer completes
4. The move is stuck a third of the way into the process, there is no progress, but the time estimate still shows what it did when it was still working. There is no usable error message, the file move cannot be cancelled (I press the button and nothing happens other than it going gray) and the remote folder cannot be unmounted (I press the button and the whole thing hangs for 30 seconds, then spews out something incomprehensible about DBus).

If you need additional information please tell me how to obtain it.