Exchange 2013 Malware Protection don't scan outgoing Malware?

Hi,

I have Exchange 2013 with Malware Protection enabled. All Logs are OK and Updates working fine. The default Malware Policy is set to "Delete all attachments and use default alert text" . 

I tested a inbound Malware Mail with eicar in attachment and the recipient Mailbox get a Text File attached with the delete infomation because Malware detection.

I tested a outbound Mail with the same eicar Testvirus attached to a external testsystem and the mail was send with include the Malware attached!

After the appaling result, i made an additional test. I tested to send internal Malware mails from Mailbox-A to Mailbox-B. The Mail was send from Mailbox-A with no interruption and only on the receive Mailbox-B the attachment was deleted.

Is there a way to debug the Malware Agent?

Has anybody tested the outgoing malware Filter?

Thanks
Nico