get the rescue application from kaser web site, and it will put things back ... I believe there is a text file that explains how to put the device into the mode where it will use the USB connection.
tom
update: the rescuer.zip is no longer available at kasercorp.net ...
If you can get ADB to work using the USB cable from a PC, you can remove the info under /data/data and /data/system and try to reboot.