LSWS and PHP parsers on other machines?

[waski]

Hello there,
I have a kind of a pre-sell question.
Is it posibble to setup LSWS on one server but parse php on other machine/machines ?
Is it possible to load-balance these php requests to machines that are least busy at the moment?
Would it be possible to direct some virtualhosts php requests to certain php machine (with different php version for example)?
And most of all - can that be setup in secure way for shared hosting enviroment?

Thanks!