Thi may be a trvial responce, but: Why not use paran's in a more standard way, at least this is a case that seems more standard to me.... I always put function param's into ()'s ... its easier to read later, imho.

$foo = 'This is a CAPITAL test, man';
$bar = 'IS A cap';
if (lc($foo) =~ lc($bar)) {
    print lc($foo), "\n", lc($bar), "\nYES\n";
}
else {
    print lc($foo), "\n", lc($bar), "\nNO\n";
}
[download]

Mbond.