Change attachment name for PO email attachment

Hi Gurus,

Please let me know the process in changing the PO attachment name which is currently 'Print data' to the actual PO number. I implemented SAP Note 191470 but I was only able to achieve changing the subject line of the email.

In the SAP Note it states:

     'Note that the values from the mail title are used to create the description for the attachment.'

I did have the mail title on the cover page text field. Also NAST-TDCOVTITLE has the PO number in it but still the attachment name/description is still 'Print data'.

Any help would be very much appreciated(of course, points will be given. ).

Thanks in Advance,

Derick