I have an MP3 file that I'm trying to figure out how I can use as my voicemail greeting. Right now, it looks like the only way to have a custom voicemail greeting is to record it on the iPhone of the voicemail you want it on. Is there any way to either upload an MP3 to AT&T's server or load the MP3 on the iPhone and have the voicemail point to it? I know I can play the MP3 back on my computer and hold my iPhone up to the speakers to record it, but a huge portion of the audio quality is lost that way. Anyone have any ideas?