I've seen this happen with websites that use javascript redirects to keep pulling you back to their page if you hit the back button. If that's the case with the website you're visiting, I'd install the noscript plugin for Firefox and activate it when you run into such a site. 

Hitting the back button quickly also sometimes does the trick.

Sorry for top-posting, Blackberry is fail for mailing lists... :(
------Original Message------
From: Josef Lowder
Sender: plug-discuss-bounces@lists.plug.phoenix.az.us
To: Plug
ReplyTo: Main PLUG discussion list
Subject: How to go back when FF refuses to go back?
Sent: Apr 25, 2009 6:26 PM

Sometimes when I go from one website to another, it seems that some
websites lock you in and won't let you use the back arrow to go back
to a previous website.  Is there some way to override that block and
get back to the immediately previous website?
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