Mine came up with /org/bluez/916/hci0. So far, so good.

4. Enter this command: hcitool scan (be sure that your bluetooth keyboard did not fall into sleep mode in the meantime and that it's still sending out information about its presence - usually indicated by blinking blue light)
After some time, you should be able to see the MAC address of your keyboard (if you don't have 10 other people having the same bluetooth keyboard in a close distance to you, you should be able to identify yours by the name)
5. Send this command:

Code:

dbus-send --system --print-reply --dest=org.bluez  /org/bluez/11984/hci0/dev_00_07_61_75_xx_xx org.bluez.Input.Connect

BUT you need to replace /org/bluez/11984/hci0 by whatever response you got in step 2 (actually the number should be only thing that will be different) and replace 00_07_61_75_xx_xx by the mac address of your keyboard from step 4 (replacing all colons by underscores)