I managed to pair my generic bluetooth mouse with my Ubuntu 15.04.
But it doesn't seem to work just yet, although the bluetooth settings says that I am connected with the mouse and the mouse's laser is responding, I the pointer is not moving at all.
Does mouse work with other machines? If so, then it's an issue with Ubuntu. To solve that, connect your wired and wireless mouse BOTH to the machine, and see if either of them works. If the wired mouse works, then it sounds like you have need to find a driver for the wireless. If the wired doesn't work, then it sounds like Ubuntu is doing a mini-crash when you connect your bluetooth mouse.
If it doesn't work with other machines, return it.