Slow tab order in Internet Explorer

In our network we have about 4 workstations that have a strange problem. All are Win95 w/ IE 5.5, all service packs installed. On all web pages where there is a login to fill out(like Hotmail) it takes a few seconds to tab over to the password box after entering your user name. This happens with all web forms, but only from tabbing from the first to the second text box. Has anybody ever come across this?