The parser (for php at least) doesn't seem to recognize "here doc" strings. For example:

$foo = <<<blahblah
This is actually
a string that is assigned to
foo as if it were all on
one line, somewhat like (") quotes
blahblah;

The string should be highlighted as a string.
Also the " in the string causes EmEdit to think a string starts in the middle of that string, which is not fun.