Description:
------------
When calling setTime() on a DateTime that has been constructed with a Weekday (e.g. new DateTime('Wednesday'))...

Calling setTime() causes the date to "jump" to the Next Sunday.  This happens on each and every call to setTime().

Reproduce code:
---------------
<?php
	$dttTest = new DateTime('Next Wednesday');
	print $dttTest->format('D M j Y - H:i:s') . '<br/>';
	/* Correctly outputs: "Wed Dec 13 2006 - 00:00:00" */

	$dttTest->setTime(12, 0, 0);
	print $dttTest->format('D M j Y - H:i:s') . '<br/>';
	/* EXPECTING: "Wed Dec 13 2006 - 12:00:00" */
	/* ACTUAL: "Sun Dec 17 2006 - 12:00:00" */

	$dttTest->setTime(12, 0, 0);
	print $dttTest->format('D M j Y - H:i:s') . '<br/>';
	/* EXPECTING: "Wed Dec 13 2006 - 12:00:00" */
	/* ACTUAL: "Sun Dec 24 2006 - 12:00:00" */
?>

Expected result:
----------------
Wed Dec 13 2006 - 00:00:00
Wed Dec 13 2006 - 12:00:00
Wed Dec 13 2006 - 12:00:00


Actual result:
--------------
Wed Dec 13 2006 - 00:00:00
Sun Dec 17 2006 - 12:00:00
Sun Dec 24 2006 - 12:00:00