dnsadmin - dns management

there are a ton of these things out there, but none of them fit my criteria of :

• free
• simple
• multi-user in a sane way
• work with bind in a non-db environment (this is the biggie)

there are plenty of commercial suites that do this, but i don't really feel like paying x dollars for something that i don't have ultimate control over. i am, however, willing to spend a godawful amount of time rolling my own.