USB devices

I have trouble connecting following USB devices to the PicoMOD7 WCE at the same time:
mouse, keyboard, stick. The stick alone seems to be detected (cannot check without mouse and kbd), mouse and kbd are working ok. But if I try to connect all 3, the behaviour depends on the order: If the mouse and kbd are connected first, they are working. If the stick is then plugged in, a dialog popps up "Unidentified USB device" with the request to type the device driver name in (tested with 3 different sticks in size and manufacturer). If the stick is plugged in first and then mouse and kbd, the mouse works, but the kbd not. No dialog popps up. No matter which port is used or wether the stick is plugged in directly or using an hub.
What can I do to get all three devices working at the same time?

Thanks, creating that parameter and setting it to 0x40000 solved the problem. I had read that message before, but because it says something about more than 5 devices I didn't imagine that 3 might already be too much.