php + apache - how to run php suid?

I use apache's suid mechanism so that all cgi scripts in a user home directory run as that user. php scripts seem to still run as the apache user (www-data with Debian) however. Obviously this represents a nasty security risk, to say nothing of complicating disk quota management. As things stand, I can't give my friends php access and still sleep well. :) Is there a mechanism for php that's similar to suid? I'm hoping I don't have to install php as cgi for each user to do this.