iCal digest authentication broken after system crash

Our XServe crashed a few days ago. It rebooted fine and all services works like before the crash. Only iCal authentication is giving me a headache. Digest authentication isn't working. Kerberos works and Basic, but I need Digest to work too. For web-authentication, everything works too, and we know the password is correct.

caldavd > access.log gives this:

127.0.0.1 - username [09/Jan/2013:14:38:15 +0200] "PROPFIND /principals/ HTTP/1.1" 207 504 "-" "Mac OS X/10.8.2 (12C60) CalendarAgent/55" i=8009 t=8.0 or=2

ApplePasswordServer.Server.log gives this:

Jan 9 2013 14:38:15 AUTH2: {0x4785feb3473967ce0000007a00000416, username} WEBDAV-DIGEST authentication failed, SASL error -13 (password incorrect).

ApplePasswordServer.Error.log gives this:

Jan 9 2013 14:38:15 client response doesn't match what we generated

Any ideas on what to look for? Caches or corrupt files to check?

Thanks!