Vacation Mail Responder

Using Vacation 1.2.7 with Postfix 2.3.3 on a CentOS 5 64bit system.

Created a testing email account and setup Vacation as per instructions. The
.forward, .vacation.db and .vacation.msg files in place.

I send a test message to the account and the message is (a) correctly
delivered to the account, and (b) delivered to the command
/usr/local/bin/vacation

e.g.,

Sep 10 23:57:30 vps6 postfix/local[3477]: 7D48DD0844:
to=<myUsername@myServer.com>, orig_to=<myUsername@myServer.com>,
relay=local, delay=0.15, delays=0.13/0.01/0/0.01, dsn=2.0.0, status=sent
(delivered to command: /usr/local/bin/vacation myUsername)

But that's all. No vacation reply is sent. Nothing else appears in the
maillog.

Everything seems OK with the mail transport, but vacation isn't doing it's
stuff.

Any ideas on how to troubleshoot?