Might be worth cooking into a Rom to give 2 side recording as standard.
Tested and working on the following Roms:
SimpleOS Xtralite v2.1, HyperDragon 4th Feb, PDA Corner Ultimate v17, v19 & v20, Anryl's 15/3 6.S rom, AthineOS WWE, WM6.5 betas (HyperDragon and PDA Corner works with HTC Voice Recorder and VITO Audio Notes, rest confirmed with VITO Audio Notes).
Download the 2_Way_Recording cab (rapidshare) *HERE*
EDIT: Made a new cab combining my 2 way recording plus the incall enable edit from pocketnow.com to enable BOTH sides to be recorded clearly from the dialer menu after a call has been established. It does not affect the ability to use a 3rd party app if you want, just gives you extra ease so you dont have to load any new programs up when you are in a call. Install the following cab to device memory, then once a call has been established just goto the dialer menu and select record. It will record in .wav format and save the recording to the Device\My Documents\Notes folder.
Download the 2_Way_Plus_InCall_Recording cab (rapidshare) *HERE*