display problem after upgrade to 6.1.0

[jmiani]

I just upgraded from 5.5.1 to 6.1.0. All went well except that when viewed from Firefox, each page has some garbage characters at the top. (See attached image). Firefox is in Quirks render mode. The same page appears fine in I.E. If I view the page source I do see a DOCTYPE declaration on the page. The garbage characters appear before DOCTYPE tag. The charset is defined in the page source as UTF-8. Firefox's default character encoding is also UTF-8. And the Apache DefaultCharSet is UTF-8. Chrome, Safari, Firefox v 3 and Firefox v 8 all show the garbage at the top, just not I.E. I am not sure what the problem is. Any one have any ideas?