Lot of MailEnable Message Delivery and no Any Failure Delivery

[ATK+]

On Plesk 6.5.2 if some one send wrong message (with wrong address ) return

MailEnable: Message delivery has been delayed.

Message is waiting at [our server].[our company].net for delivery to jsjjsjjsjsjsjs.com
Reason: Mail Server for jsjjsjjsjsjsjs.com could not be contacted at this time. MailEnable will keep trying to deliver this message and will notify you of any progress.

instead generate a "MailEnable: Message Delivery Failure." and delete message from queue .
I check DNS ( It's OK ) , MailEnable Config ( It's ok ) .
Any body can help me or any Idea .

 

[ATK+]

Some of my problem solved

I tested some configure on MailEnable MMC an was so attractive for me .
When i set "Failed message lifetime" to 5 hour all message after this time that can't connect to out mail server returned with failed delivery and i delete some sub key in MailEnable key and after that i just receive one delay delivery ( all this problem solved in new version of MailEnable 1.81 ).
when i set again "Failed message lifetime" to 21 hour (default is 36), we don't receive any failed deliver again after that i set again to 10 hour and our problem solved ( any body know what what happen ?).
But why when i send mail with wrong domain address mail enable don t generate failed delivery immediately ( i don't have this problem on my test Plesk server ) and all this problem exit before we get this servers ( 2 server with 2same problem ).
ATK <)