[support] Accounts w/no email address

I've googled a bit for this. Other than some old patching-core discussions from 2008, I didn't come up with anything. The ability to create accounts without email addresses in D6 is required. Is there a module with this capability? It would have to permit accounts to get email addresses later (although we could do that via CCK if necessary). This needs to be a regular module, not a core patch or hack of any kind, as I will not be maintaining this site going forward, and short of upgrades, I do not expect the future maintainer to be capable of migrating custom code. Thanks Luke