redirecting emails to multiple users

[skaigonakeryon]

We're running a multi server installation and have added a header check config file to opt/zimbra/conf so emails coming from a specific external email to any of our users will be redirected to one specific user. This is working as it should. But we can't add a second address which has become necessary. If we add a second address with a , after the first, the email won't be delivered at all. We also tried setting up a distribution list, add the two recipients to that list and put the dl as the address the email should be redirected to but it doesn't get delivered either.

Does anyone have any idea why the mails don't get delivered and how to fix this?