[daiyi666@yahoo.com]

Sorry, Leopard Mail seems to have lost the ability to add attachments!

PS I squashed that bug and sent you the report. In Leopard Mail, you may have to make sure a message has either existing text (reply or composed message) or that you hit return once in any empty message to insert attachments (dragging does not work either). Seems Mail can't discern the end of a blank message.