Search function permalinks – /search/

I’ve set my search form up as follows using…

<form id="searchform" action="<?php echo $_SERVER['PHP_SELF']; ?>" method="get">

…and have search.php in place.

This works fine but the results page functions under /index.php?s=test

How can I change the search so it works as /search/test/ etc. the same as my other “pretty” permalinks?

Also, when the search box is empty and it’s submitted – I get only ?s= – without index.php. This causes a different page (the absolute root) to show as my site is located in /home/ for now.

Can anyone help?

Thanks a lot