links is dead, so I don't know if normal bluetooth HID mouse works with nokia n9.
I bought Microsoft Designer Bluetooth Mouse for one of the coworkers (for Windows Tablet), and wonders if its possible to connect it to n9. I guess that no(because it requires BlueTooth 4.0). So probably I need to port new kernel and BlueZ 5.x(would it be very hard?)
I read once in conjunction with connecting a bluetooth keyboard to the N9, that someone tested the same with a bluetooth mouse and did not have fun with it. He reported very strange behaviour like heavy lags, unpredictable freezes and even instant reboots if I recall correctly.