I've tried to get the hack working with my blog and when I did it would change the keywords of my main page to the one that I used for the single post. I want to be able to have a fixed set of keywords for my index but then have each category have a different set. I've created stub files for each of my categories ie.
http://www.executivefraud.com/_Accounting_Scandal.php
and when I try to modify the keywords by adding it at the top of the stub file it returns this error:

Warning: Cannot modify header information - headers already sent by (output started at /home/qualiub6/public_html/executivefraud/_Accounting_Scandal.php:2) in /home/qualiub6/public_html/executivefraud/inc/MODEL/skins/_skin.funcs.php on line 71

Any thoughts on how I could work around this, I currently have the keywords in _main.php and I've tried to change them around by removing them from there and putting them only in the stub files but didn't have any luck & received the same errors. Please help