[Freeswitch-users] Change voicemail, example code available?

I would like to change how the voicemail acts in FreeSwitch. But as I've figured out it's hardcoded into Mod_voicemail. So I would like to make my own via an IVR. Does anyone know any sample code for a simple voicemail, that I can use for reference? One thing I would like to change is for example that it shouldn't hang up on wrong ID's, but give one 3 tries to enter a correct ID.