Site works fine in firefox, but not in internet explorer

Having some trouble with my site…

http://www.insomber.cjb.net

You’re supposed to be able to click that writing button and have it open a centered, chromeless window of this page…

http://www.insomber2.cjb.net

It works fine in firefox, but when you click the button in IE to open the second page, it says that it cant be found. (havent tried it in netscape or any other browsers yet).

Any ideas?