How to fix a corrupt duplicate DB?

[Steinar Bang]

Platform: Intel pentium II, debian etch
	  exim 3.36-18.2 
	  cyrus21-imapd 2.1.18-5.1
	  cyrus21-common 2.1.18-5.1
	  cyrus21-admin  2.1.18-5.1

Mail delivery to my cyrus imapd has become flaky.  Some messages come
through, some are bounced with this message:
 This message was created automatically by mail delivery software (Exim).

 A message that you sent could not be delivered to one or more of its
 recipients. This is a permanent error. The following address(es) failed:

  sb at localhost
    pipe delivery process timed out

Some generate the above bounce message, even though they actually go
through.

In the /var/log/mail.err file I see lines like this:
Aug  3 11:12:15 doohan cyrus/lmtpd[26302]: DBERROR: error fetching <495295EE69BB4B4AAE73D1B0D8AD5518018E83E8 at ATLAS.somecompany.int>: Invalid argument
Aug  3 11:12:15 doohan cyrus/lmtpd[26302]: duplicate_check: error looking up <495295EE69BB4B4AAE73D1B0D8AD5518018E83E8 at ATLAS.somecompany.int>/user.sb.SPAM: cyrusdb error

I'm guessing my duplicate DB has become corrupted...?  Is there a way
to regenerate it?  Is there a way to scrap it and start with a fresh
database? 

I've run cyrreconstruct in the hope that it would magically fix
things, but it didn't help.

Thanx!


- Steinar