what I said here:
" then make your java function construct php variables to hold whatever you need, the data the checkboxes pass through the form would not be needed, and you could also have the java construct hidden fields to pass the calculated data to the next script"
was in response to a different thread, I was juggling a few at one time, sorry for the confusion...
you shouldnt need JavaScript for this...maybe try this, I dont usually try to submit forms to different urls...but I know it can be done...I have used many scripts hosted elsewhere in the past such as mailing lists before I could write my own...
Try this:
<form action="http://site.com/dir/script.php" method="post" enctype="multipart/form-data">
I think the enctype is important for security and otherwise, if your script simply displays the page...and that page is php, that means that there must be some execution going on...