Cool. That makes it easier to answer your questions because each point release 3.X is different than the last.
In the admin you can go to patch/upgrade and enter it into the Apply SQL Patch, Queries box.
Please do a FULL backup of your database before attempting this.
If the database patches then you are laughing. This is an easy and excellent mod. They included similar email mods in the 4.0 beta.
There is no reason why it shouldn't patch but if you have a problem, just post back here again!
