aptana3 - Adding a PHP expression warning exception in CSS validator -

i working php variables in css files. cannot figure out how add warning exception css validator <\?php echo $purple; ?>

i tried .*<\?php.*\?> , .*\<\?php.*\?>. error keeps poping out @ < syntax error: unexpected token "<"

i believe when add css validator exceptions, make regular expression error or warning text, not cause of it. e.g., don't add exception .*<\?php.*\?>, add syntax error: unexpected token "<". see page examples: http://morganizeit.com/2008/04/configure-aptana-to-ignore-css-hacks/

it worth pointing out if regular expression doesn't seem have effect on error/warning working on, may adding wrong validator there multiple ones @ work in given editor. example, when edit css, warnings css syntax validator , errors w3c stylesheet validator. if expression not working in 1 of those, try on other. can determine error's source disabling validator temporarily , seeing if warning/error quits.