safe PHP scripts execution?

[Marcin Owsiany <porridge@pandora.info.bielsko.pl>]

Hi!

Does anybody happen to know some feature that would allow PHP
scripts to be executed by a user different than www-data?
Something like suexec...

Or am I wrong thinking that you can't write to your files
using PHP without either:
 1. chmod o+w file
or
 2. sudo adduser user www-data; chmod g+w file
or
 3. administrator intervence for each file
    (chgrp www-data file ; chmod g+w file)

(All three of them are bad security, if the user wants to
protect the file from being written to by others)

Marcin
PS: Sorry for the strange language. I'm sleepy :-\
-- 
Marcin Owsiany <porridge@pandora.info.bielsko.pl>
http://student.uci.agh.edu.pl/~porridge/
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