you post to one file - say - script1.php
it does some stuff, then you want to use another script (for whatever reason)
you could use exec() to execute the second one, script2.php
actually after more thought, scrub that, after the first one has done it's thing, as long as you've not outputted to the browser using the first script (no print statements etc)
you could then use
header("Location: http://blah.com/script2.php?some=paramters&are=placed&here=true");
this will then 'redirect' you to your second script
It all depends on your logic though, i.e. why it was decided to pass some form values into two scripts
hth
Bealers