This little gem will make the JasJar vibrate when you press the number while dialing a number.

Although originally for an i-mate Apache this works with the JasJar.

Using a registry editor navigate to the following keys and follow the directions. Do this for each of the listed registy keys

1. Rename Standard DWORD parameter "Sound" to "Sound1"
2. Create new String Parameter "Sound"
3. Assign value *vibrate* to this new parameter.

HKEY_CURRENT_USER\ControlPanel\Sounds\Dtmf#
HKEY_CURRENT_USER\ControlPanel\Sounds\Dtmf*
HKEY_CURRENT_USER\ControlPanel\Sounds\Dtmf0
HKEY_CURRENT_USER\ControlPanel\Sounds\Dtmf1
HKEY_CURRENT_USER\ControlPanel\Sounds\Dtmf2
HKEY_CURRENT_USER\ControlPanel\Sounds\Dtmf3
HKEY_CURRENT_USER\ControlPanel\Sounds\Dtmf4
HKEY_CURRENT_USER\ControlPanel\Sounds\Dtmf5
HKEY_CURRENT_USER\ControlPanel\Sounds\Dtmf6
HKEY_CURRENT_USER\ControlPanel\Sounds\Dtmf7
HKEY_CURRENT_USER\ControlPanel\Sounds\Dtmf8
HKEY_CURRENT_USER\ControlPanel\Sounds\Dtmf9

Sourced from: http://www.mdatweak.com/tweak_detail.php?tweak=14 

[Moderator edit (MF): hyperlinked)