These forums are locked and archived, but all topics have been migrated to the new forum. You can search for this topic on the new forum: Search for Money4u Billing Manager includes support for Virtualmin on the new forum.
I've just received word from Collin Schwagele of a new billing system that he's developing that supports Virtualmin GPL and Professional (as well as one other virtual host administration system that shall remain nameless). I know there's a lot of interest in billing systems, so I thought I'd mention it here as well as adding it to the FAQ about billing systems.
It looks like a pretty early release, but more choice is usually a good thing, and hopefully it will develop quickly.
Here's the link:
If anyone tries it out, be sure to let us know how it goes in the forums.