Ok, I gonna answer some of my questions myself:
- "Data abort" occurs when calling getMessage() of Exception-Class. Without this call, the VM doesn't hang up.
- connecting to a device which is not yet a known device, can be done by Bluetooth.connect( byte addr ), where addr must be an array containing 12 values. Bluetooth-adresses contain 6 hex-values. These 6 must be split into 12.