Shell hosting and apache pid

[madcat87]

I am having a server and multiple users can connect to it with ssh.They have a maildir and a public_html dir in their HOMEDIRs.The problem is with the execution of php scripts through Apache. The problem is that the php scripts executed in ~/public_html are executed with the privilege of the Apache user Process.So every user can execute a script that can read in the homedirs of the other users.Is there any way to make Apache to execute this php files with the ID of the Owner not the user Apache apache is running as ?

Thanks

[eaglex]