Firefox 3 introduces a new behavior when your doctype is XHTML Strict; certain tags that do not allow minimization as per the spec no longer close anyway. For example, if you use a <script src="blah.js" />
tag in your heading, Firefox 3 will take the whole rest of the page as a script, which will result in a blank page. This is good as it enforces standards compliance, however jspx minimizes tags, so you may have <script src="blah.js"></script>
on your page, but the actual rendered page will minimize it.
There are many ways to fix this issue by playing tricks on jspx, I recommend:
<script src="blah.js"><!-- //prevent jspx minimization --></script>
This reminds me when I'm working on the code why that comment is there. Hopefully this will be fixed in the jspx spec at some point.