Well, kind of, but nothing that can't be fixed
First make sure you uploaded the correct robots.txt, excluding in your case all phpBB vanilla URLs as suggested in the mod rewrite release thread (the one you are using

), eventually the able2know ones as they may have been spidered as well.
Then,
DO NOT use the complete removal of your site Google Tool !
Just go there :
http://www.google.com/support/webmaster ... lude_pages
Login to your Google account and use the (sorry, but with my IP Google does not allow me to see the page in English

) "something like automated link removal tool", based on you robots.txt.
Basically, You just have to Disallow all unwanted URLs in your robots.txt and submit it to this Google tool.
Google will then take away all of the Disallowed URL at once and other search engines will do the same when they will find your robots.txt file, it's just not automated to be all done at once, but they'll disappear quite fast from cache and completely with time from every search engine (the decent ones) to have spidered them.
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