This simple frameset is not working in Firefox (IE7, 8, Chrome is okay). main doesn't appear but footer does. There's a frame window divider flush to the top of the screen, but even after pulling that divider down, no main content is shown.
It's validated under its DOCTYPE. Any ideas?
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title></title>
<meta http-equiv="cache-control" content="no-cache"/>
<meta http-equiv="pragma" content="no-cache"/>
</head>
<frameset rows="*,33">
<frame name="main" src="internalpage.html" />
<frame name="footer" src="http://www.example.com/externalpage.html" />
</frameset>
</html>