Suppress vibrate when docked?

Question

When I dock my iPhone in the charger (desk stand), it briefly chimes to say it's charging. If it's on silent, then it vibrates instead of chiming. When I go to bed and put the phone in the bedside charger, the noise from either is very annoying.

I want to suppress the vibrate-on-charge. How can I do that?

It's already jailbroken so suggestions in that genre are fine too.