Comment 3 for bug 134752

OK so I tried the new network card already. It was a 3com 905-tx. It made no difference.
However recently I installed the Kubuntu KDE desktop on my system to see if it would make any difference in a few areas. One are being this.
The difference it made was that Konqueror performs perfectly after shutting down the system and Nautilus alone has this issue. Dang since I like nautilus better.

What interesting out my test is this.
I shut down the server and tested nautilus, as soon as the shares became unavailable nautilus had the problem.
I tried Konqueror and it was fast.
I then restarted the server, as soon as the login screen came for Ubuntu, shares available, nautilus sprang to life again.
 No unmounting, no ctrl, alt backspace to restart things. It is totally and completely dependant on the shares being available or unavailable.
So for you if you have networking issues ie. your connection drops you would have the same problems.

PS on a curiosity note, are you crossover cable to connect both your computers? straight computer to computer? If so ditch that setup, buy a cheap hub/switch and watch your connection problems disappear. If your not setup this way I have no idea why your connection keeps dropping.