Error getting while sending the Mails using 'SO_NEW_DOCUMENT_ATT_SEND_API1'

Hi ALL,

I HAVE THE REQUIREMENT AS SEND A REPORT AS A MAIL. IAM USING FM 'SO_NEW_DOCUMENT_ATT_SEND_API1' WHILE EXECUTING ITS NOT SHOWING ANY ERROR. BUT IAM NOT GETTING ANY MAIL. I CHECKED IN 'SOST' TCODE. THERE I SEE A MESSAGE LIKE 'CANNOT PROCESS THE MSG TYPE IN SAP SYSTEM'. PLS TELL ME THE WHAT IS THE PROBLE.