smtpd not starting because of /etc/aliases.db

[goppegard]

I have a fresh install of ZCS NE 6.0.1 on OS X Server 10.5.8. Postfix doesn't respond when telneting to port 25 and the following error is logged:

Sep 16 19:07:59 zimbra postfix/smtpd[52879]: fatal: open database /etc/aliases.db: Invalid argument
Sep 16 19:08:00 zimbra postfix/master[52106]: warning: process /opt/zimbra/postfix/libexec/smtpd pid 52879 exit status 1
Sep 16 19:08:00 zimbra postfix/master[52106]: warning: /opt/zimbra/postfix/libexec/smtpd: bad command startup -- throttling

I've tried removing "alias_maps = hash:/etc/aliases" from /opt/zimbra/postfix/conf/main.cf, but the config file is re-generated by zmmtaconfig upon restart. Same goes for removing the POSTCONF alias_maps from /opt/zimbra/conf/zmmta.cf.

Any suggestions on this issue?