customization to PHPWeby and possibly WPMU/b2e

I would like to integrate phpweby ([login to view URL]) with multi user/website builder (such as WPMU). The idea is a web directory with 2 types of users: 1) customers signs up and automatically received updates/newsletter from site 2) businesses signs up and is allocated their own mini/micro sites like WPMU/b2e - but not in blog style. ps. extension to the CB - community builder or SOBI2 in joomla seem good, or WPMU or B2E