Here is a small example of how I have embedded PHP into a javascript in order to generate a rollover.
if (document.images) { // Active Images
img1on = new Image();
<?php
if ($directory=="home")
{ echo "img1on.src = \"headers/images/navigation/home_tab_orange.jpg\";"; }
else
{ echo "img1on.src = \"headers/images/navigation/home_tab_green.jpg\";"; }
?>
img1off = new Image();
<?php
if ($directory=="home")
{ echo "img1off.src = \"headers/images/navigation/home_tab_orange.jpg\";"; }
else
{ echo "img1off.src = \"headers/images/navigation/home_tab_grey.jpg\";"; }
}
?>