How do you cause a longer vibration from System sounds default vibration

I want to create 开发者_JAVA百科a vibration but not of the normal length

It can't be done with the official SDK. The only way to trigger vibration is using a call to the following function, which unfortunately does not take any other parameters.

AudioServicesPlayAlertSound(kSystemSoundID_Vibrate) 

Maybe there's a way to do it for jailbroken iPhones, but no that I'm aware of.