||Possible, not necessarily easy.
I think you'd have to save the message as an .eml and then you'd send a message with the .eml as an attachment.|
You could do this via a script and you could assign that script to one of the buttons on the toolbar. The script would save the message as an ".eml" file and then start a new message attaching that ".eml" file as an attachment.
It would leave the message open in the compose window (via the EditMessage command), you would have to select the recipient(s) and then send the message.