You could also look at using SME server (see contribs.org). Open source SBS type system with a large active user community. There is also a selection of user contributions and HowTos including incorporating Asterisk. It will also run much more efficiently on the your existing hardware that Microsoft SBS.
Slashdot Mirror
You could also look at using SME server (see contribs.org). Open source SBS type system with a large active user community. There is also a selection of user contributions and HowTos including incorporating Asterisk. It will also run much more efficiently on the your existing hardware that Microsoft SBS.