Glad to hear that the site is still up and running. A lot of sysadmins got to understand how an OS ticks with Amiga, I for one.
If the main issue is PHP4 compatibility, then I would be happy to offer some server space to host amiga.org for free (assuming the traffic isn't huge) or a nominal fee if there is a lot of traffic.
I have a managed Ubuntu server running from the UK on a good pipe. I wouldn't have time to do any admin on it but I could set up the services so that it can be administered by the existing site admin(s).
I don't want to get in the way of an upgrade... but I do come from the "if it aint broke don't fix it" school of computing.
Cheers