JC,
Another way to solve this problem is to use output buffering. Output buffering acn be turned on in the php.ini file, but does cause a performance hit. If you don't use alot of cookies or headers on your site, take a look at the output buffering functions in the PHP Function Reference:
http://www.php.net/manual/en/ref.outcontrol.php
Some of the functions are only available in PHP4, but I think there are work arounds if upgrading isn't an option. Sorry, can't remember any links:-( Hope this helps!!
Cheers,
Geoff A. Virgo