Microsoft IntelliMouse trackball

Hi,

I have a trackball that connects to my Win95 machine. This version of 95 states that it is USB compatible. The mouse has a USB connector that plugs into a small PS/2 mouse adapter, which plugs into the PC. The mouse is sparatic on startup, but if you unplug the mouse, then plug it back in it works fine once the PC has reached the desktop.

I tried using just the USB port but the mouse shows no activity. Any ideas? Thanks in advance for your help and suggestions!!!