Funny hand from yesterday playing with Jeff against a non-established pair on BBO. 

In 2nd, unfavorable, you hold:

K96 / QT5 / KJ963 / J6

I might open 2 Diamonds in 1st favorable, and 1 Diamond in 3rd not vul, but 2nd seat I'm pretty disciplined and at unfavorable, it's not remotely close.  Anyway, this isn't a bidding problem.  The auction proceeded:

P-P-1C-P
1H-P-2H-P
3C-P-3H-P
3S-P-4H-P

What do you lead?

What do you lead if the 3 Spade bidder self-alerts and describes it as 'asks stop'?

My cynicism got the best of me on this one.  Why is this guy drawing me a roadmap to the best lead?  I'd be on a pure guess if he had just bid 4 Hearts and it's unlikely that his partner would interpret his 3 Spades bid correctly anyway.  I stabbed a diamond and declarer rode it around to his queen and was home.  A spade lead and a diamond switch leads to a quick down 1.