You can do either or both of the following.
Apply the checkuser patch. There is a modified one to work with vpopmail at
http://www.shupp.org/ I have it working on 5.3.20 with mysql and it works
echo doublebounce >/var/qmail/control/doublebounceto
echo '#' >/var/qmail/alias/.qmail-doublebounce
The second one is a good idea anyway if you have a high volume server cause
it sends the doublebounce's to null.
>From: Thomas Lojmann Jorgensen [mailto:[EMAIL PROTECTED]
>Sent: Friday, 1 August 2003 11:34 PM
>To: [EMAIL PROTECTED]
>Subject: [vchkpw] I'm tiret of bounce mail that is bounced...!
>When someone is sending a mail to a user that dosen't exist on my
>domain, it send a mail return to tell the sender that the
>That is fine, but when the reply adress in the senders mail isen't a
>valdi e-mail then the "postmaster" recive a mail from the
>mailer-deamon at the domain, etc.:
>Hi. This is the qmail-send program at mydomain.com
>I tried to deliver a bounce message to this address, but the
>220.127.116.11 does not like recipient.
>Remote host said: 550 <[EMAIL PROTECTED]>: User unknown in
>local recipient table
>Giving up on 18.104.22.168.
>I'm tiret of this mails, isen't it possible to disabl this function
>Have a nice weekend :)