I get the following error when doing a 'aptitude update' on a Debian 
Etch box.  Before I email ftp-master@??? with the problem am I 
doing something stupid?  I have repeatedly run aptitude update and the 
error persists...
Simon C.
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Hi Simon,
I suspect your answer lays somewhere down this path:
http://linux.derkeiler.com/Mailing-Lists/Debian/2007-09/msg02056.html
(Check the follow up mail [SOLVED] too)
Although why your keys are no longer usable is a mystery - corruption?
Sean