There have been some questions about how the pop-up blocker included with IE6.0 in XP SP2 works.

Jeff Davis has a post that talks about what constitutes a “user initiated action” and what you will want to look for to make sure your app still works.

*Q:* Why does IE6 + XP SP2 block new windows launched from my onMouseDown handler?
*A:* We wanted Pop-up Blocker to allow new windows launched as a result of a user initiated action. We defined ‘user initiated action’ as a click (or keypress). A click is a mouseDown followed by a mouseUp. So you can launch user initiated windows from an onMouseUp or onClick handler, but not a MouseDown handler.