Not able to See Message section in SUS PO

Dear Experts,

We are implementing MM-SUS scenario our Version is SRM 7 and EHP 3 ....

We are able to replicate pos in SUS. but we are not able to see message section in portal both at item as well as header level.

We are sending text message from SAP R3 which i can see in XML but i'm not able to see in Purchase order  in section MESSAGE FROM PURCHASER ..

Also when we create response to the PO its also not allowing to message to purchaser.

Please advice.

Thanks and Regards

Sanjeev.