PHP will not accomplish that. PHP can change the page before it is sent to the viewer, but not after (making a menu pop out is changing things on the page).
There is a method of doing this without any Javascript. See this: http://www.xs4all.nl/~peterned/examples/cssmenu.html .
And you can see lots of non-javascript menus here: http://css.maxdesign.com.au/listamatic/ .