Asterisk as a Mobcasting Tool?

Over the last few days I've been trying to learn more about various types of open source telephony software to see if any of them could be built upon as a mobcasting interface -- voicemail software that could allow someone to call a local telephone number and create, as well as listen to, podcasts. I've written a lot about my experiments with audlink.com and audioblogger.com as mobile podcasting tools, but they both require you to call a long telephone number in the US. Ideally, we really need to have a tool that could be installed at low cost on a local server, anywhere in the world, and allow people to make a telephone call to post or retrieve podcasts from it.

That's why I'm really curious about an open source software package called Asterisk.

Asterisk is a fully functional open source PBX system with VoIP capabilities. It supports voicemail, call directories, conference calls and many other features, and allows users to build new scripts to connect it with the Internet. It was primarily developed on GNU/Linux for x/86, but apparently runs on GNU/Linux for PPC along with OpenBSD, FreeBSD, and Mac OSX.

To be honest, I know almost nothing about PBX systems, so I'm hoping some of you might be able to help me evaluate it, and perhaps test it out. Participants in one of the Asterisk user forums seem to think it would be easy to set up a script to connect it with a blog, but from a technical point of view, this is way over my head. I'm hoping some of them might volunteer to help me, but we'll have to see how that goes.

So, for those of you who are interested in mobile phone podcasting, I'd love to get your thoughts on this, particularly if you know a lot about PBX systems, VoIP, etc.