How to disconnect a user

Someone's asking this in the PHPBuilder forums:

http://www.phpbuilder.com/board/showthread.php?s=e35a83518b040c2b4db0c7ef3867ab40&threadid=10244626

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Hi all

Is there a way to disconnect users from a D.B in postgresql rather than
kill -9 the pid user?

thanks in advance

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Doesn't seem to me that there's any way to do it...

Chris