@Pate: Thank you for your welcome. And great that it could be possible: Here is how the controllers show up:
I have two of the same controllers, speedlink thunderstrike (not the best

) on controller shows up like:
in the dev/input map it shows up like "js0" and "event3" (also have mouse and keyboard) and in dev/input/by-path it shows up like "platform-bcm2708_usb-usb-0:1.3.2:1.0-joystick" and "platform-bcm2708_usb-usb-0:1.3.2:1.0-event-joystick" and in dev/input/by-id as "usb-DragonRise_Inc._Generic_USB_Joystick-joystick" and "usb-DragonRise_Inc._Generic_USB_Joystick-event-joystick"
The other controller shows up like:
as "js1" and "event4" in dev/input
and as "platform-bcm2708_usb-usb-0:1.3.4.1:1.0-joystick" and "platform-bcm2708_usb-usb-0:1.3.4.1:1.0-event-joystick" in dev/input/by-path
and it isn't really showing up in dev/input/by-id, there are still the same files as with one controller, so in by id there is nog way to see there are two controllers
I hope this is helpfull! If I can do something else, just let me know!