I use IE6 as well.
The forums that Alucard and I use, pop up an ad everytime a page loads. Normally this ad opens in a new window. So, the problem you are having is that the ad is opening in the same window, instead of a new one.
I\'ve never seen this problem before and have no idea how to fix it. If I figure it out, I\'ll let you know.
Do you use some sort of pop-up killer?
EDIT: When the ad comes up, if you hit \"back\" on your browser, you should be taken back to the forum. This would be quite annoying however, because you would have to do it everytime a page loads.
Anyway, this is getting a bit off-top, back to the dark empire...