I have a Targus Uni. on a 5500 with Sharp 3.1. I loaded the IRK package and had no problem.
You\'re right that there\'s no on/off; when the keyboard is open, it\'s on. There is, however, an on/off switch on the Targus settings. When you choose Targus (from among the data entry choices), a settings bar should come up and the default is \"off\". Choose \"on\" and it should work. At least it does with Sharp3.1.