$('div:has("p+p')') causes browser to freeze with jQuery 1.3

$('div:has("p+p')') causes browser to freeze with jQuery 1.3


I get:
"A script on this page may be busy, or it may have stopped responding.
You can stop the script now, open the script in the debugger, or let
the script continue."
With the code:
$('div:has("p+p')')
And the HTML:
<div>

1

</div>
This worked fine with jQuery 1.2.6.
Test case: http://jsbin.com/atiha/edit
Tested in FF3, IE7 and Chrome.
Is this a bug with jQuery 1.3 or is the syntax wrong?