Hmmm haven tried it to be frank but M sure it is possible ...
There are couple of options available to you, look into a app called mRouter *developer.intuwave.com/Downloads/m-Router
Additionally you can look at a tool called Gnubox ... I know it allows you to achieve it over IR and Bluetooth but since it's an GPL someone should have certainly worked out the way to use this over Com port ...
These are just starters (what I could find in 2 mins) .... google and u'll find more .... So pull up ur socks nd GO .......