Index: wp-includes/kses.php
===================================================================
--- wp-includes/kses.php	(revision 17335)
+++ wp-includes/kses.php	(working copy)
@@ -1404,7 +1404,7 @@
 		if ( strpos( $css_item, ':' ) === false ) {
 			$found = true;
 		} else {
-			$parts = split( ':', $css_item );
+			$parts = explode( ':', $css_item );
 			if ( in_array( trim( $parts[0] ), $allowed_attr ) )
 				$found = true;
 		}