"Bad user" on Solaris 10 crontab

An account used for an application could not run its cron jobs. In /var/cron/log all I could see was:

! bad user (wondapp) Tue Nov 13 03:23:00 2007

I checked /etc/cron.allow (which didn't exist) and the user's shell in /etc/passwd but the problem turned out to be in /etc/shadow. The user was listed as:

wondapp:*LK*:::::::

This was because a password was never set for it. I just edited it to read:

wondapp:NP:::::::

Which still doesn't make a valid password but doesn't lock-out the account either. Cron jobs for wondapp work now.