Born To Rune! Yes! ROFL

There's a play, Arcadia, by Tom Stoppard, where they talk about hahas - always makes me laugh:

A: "...I think he's in the ha-ha."
B (unexpectedly): "Ha-HA!" (emphasis on the 2nd 'ha')
A: "What?"
B: "I always thought it should be pronounced ha-HA! Because when the ground suddenly gives way beneath your feet, you're not going to go 'ha-ha', are you? You're going to go 'ha-HA!', or more likely 'Bloody 'ell!'"

(And, bollox, you're right, Zack=Jack.)