Here is a workaround that might serve your purpose.
Right click on the account you are sending from, select Properties and then the Advance Tab. At the bottom select to Leave a copy of message on server. Then when you send the message and you receive it back it will remain on the server and then go to your other computer and you should also receive a copy. Not very elegant but may get the job done. It also has an option to remove it from the server after a specified number of days.