A small problem since migration : we have a domain (foo.com) and the account support@foo.com is redirected to another server (helpdesk software) on a subdomain : @support.foo.com.

Redirection is done using dns/mx (on the zimbra server).

Now if I use classic linux mail on the zimbra server (support@foo.com) it get's there ! But if I add the entry support@support.foo.com to the forward element of the Zimbra account, it's my ISP smtp that tells me it's unknown.. considering that this is internal I quite agree It seems that Zimbra sends it out into the wild

What am I doing wrong ?

Many thanks