Problems with Mini-Dock and ps/2 mouse

[kapesa]

I have problem with T40 and Minidock(2878). When a mouse is connected to ps/2 port it stops working after a couple minutes. Then after I have reconnect the mouse it start working until it jams again. I have tested this using several ps/2 mouse devices and all of them have same problem. If I use usb mouse it works fine so the problem is related to ps/2 in mini dock. Also other connections are working fine and I have googled the problem without any luck. I wonder if you could help me.

EDIT:
I can't find any error logs. Do you know where to find one?
The problem is not related to operating system because I have dual boot system, XPpro and Ubuntu. This sticking occurs with both os.