PHP - Php Blogging

Hi Guys,

I've been looking for a clone script for this, but can't seem to find one, so I'll more than likely need to code it (unless you know of a clone). Basically, what I want to do is to have a tumblr like clone, where a user signs up, chooses a username, password and blog address (a subdomain of the root, or in a different folder (eg. www.gdfgdfg.com/blognamehere or www.blognamehere.gfdgdgdgg.com)), and then they are able to blog from a user panel (the software will be auto-installed to the sub-domain upon account creation).

Thanks,
Jack