IE Button Resizing with Page

 I have an AJAX Tab Container and just above it, in the upper right corner, there is a plain-old ASP button. In Firefox (3.0.1) It appears where it should, but in IE7 (and IE6) the button seems to follow the right edge of the page as it resizes, essentially making is move around with the window. The tab container, however, stay put where I meant it to be. I'm pretty new at ASP.NET and AJAX, and any help would be greatly appreciated.
 
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