[sork] Problem with vacation and postfix

[Gustavo Verduzco Vazquez]

Hi!

I installed the debian package "vacation" and the horde module 
"vacation-cvs releng_2" and when I set a vacation message on my inbox the 
people who sends me mail get the message bounced with the following error:

This is the Postfix program at host some.domain.com.
I'm sorry to have to inform you that the message returned
below could not be delivered to one or more destinations.
For further assistance, please send mail to <postmaster>
If you do so, please include this problem report. You can
delete your own text from the message returned below.
The Postfix program

<username@some.domain.com>: Command died with status 1:
"/usr/local/bin/vacation username"

Any ideas of what might be going wrong?

Thank you in advance!