Yep, it sounds like a mod_sec problem. It's pretty easy to disable; the following is a link to the thread which contains the code on how to disable mod_sec:
mod_security Fix. Note: the thread has been stuck in the PHP hosting forum so if anyone ever needs it in the future, it's pretty easy to get to.
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Regards,
Josh Hold
eUKhost Blog: Over 1000 Computer Related Articles to Sink Your Teeth Into!
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