preg_split vs. perl-style split and capturing ()

[Anon]

Does anyone know if/how capturing () works in preg_split?...check this out

$string = "this is a test";

in perl...
split(/(is.*a)/,$string);

results "this ", "is a", " test"

in php...
preg_split('/(is.*a)/',$string)'

results "this ", " test"

The captured "is a" is missing from the php result array...

Thanks
Brian