I just developed a new application that runs on the iPhone and iPod touch that works with freePBX. Much like how you check your voicemail on your iPhone, AsteriskVM allows you visually see and listen to your voicemails. You can delete voicemails on the fly and skip ahead or backward to any point of the voicemail.
See it at http://www.waterclosetgames.com/applications or on iTunes at http://itunes.apple.com/app/asteriskvm/id353332733?mt=8
if you have any questions or comments feel free to ask me http://www.waterclosetgames.com/contactus