Accept An Out Parameter In Ajax?

I have a static function in the aspx page with this signature:

public static bool UserNeedsToBeAlertedPwdReset(out DateTime dtExpires)
{
DateTime dt = DateTime.MivValue;
return true;
}

So I want to call this function from the client side, using the jQuery Ajax. How do I get a hold of the out value? Edit Alternatevly I could check for nulls if this is possible with Ajax + jQuery like that:

ublic static DateTime? UserNeedsToBeAlertedPwdReset()
{
if(blah)
return null;
return DateTime.Now;
}