Hello,
It is likely you are hitting the bug described in the KBA 2055436 - After upgrading to SP12 Ad Hoc EarlyWatch Alert stops working / corrections in sap note 2055455 - SDCCN: Refresh session task does not process manually created EWA service sessions
it would be useful if SAP added the note 2055455 in the solman central note 1969109 - SAP Solution Manager 7.1 SP12 - Basic functions... and it also looks like the note 2055455 applies to SP11 so could be added to 1933506 - SAP Solution Manager 7.1 SP11 - Basic functions...
Hope this helps
best regards