Screen jump on mouseover active tab

Project:acSimple
Version:1.0
Component:User interface
Category:bug report
Priority:critical
Assigned:Unassigned
Status:new
Description

When doing a mouseover on the active tab, the whole screen jumps a little bit up. I don't know the reason why, just the circumstance.

I tested it on:
* Windows XP (SP2)
* IE 6

PS I couldn't find how to react ...

Hello Koko,

what's your OS and browser ?