Although Macally seems not to allow the name of the iKey4 to cross its lips any more, I found a generalized FAQ page about iKey keyboards.

The mouse freeze issue is related to timing implementation between the host Mac CPU, the keyboard/hub and the mouse during the sleep/wake-up sequence. Clicking the mouse will wake up the keyboard/hub and the host Mac CPU. In response, the Mac CPU will acknowledge that the keyboard/hub is awake, but never acknowledges the mouse. The mouse continues to stay in the sleep mode and appears to be frozen.
As workaround, please wake your system by using the keyboard only. If by accident you click the mouse while the system is in sleep, please unplug the mouse from the keyboard and re-plug it.

Click to expand...

The recommended workaround is not effective for me, using an Apple optical mouse, but the fault is not a freeze but a delay in waking. The workaround may be effective for a compatible Macally mouse, but not for the Mac Pro.

Another oddity is that the iKey's keyboard hub has ample power available for the mouse from either USB port, but will not power/recognize a SanDisk Cruzer Titanium 1GB thumb drive, whether or not the mouse is also attached. One blink of the Cruzer's LED is followed by absolutely nowt. Nowhere on the iKey's original box is there a statement about the power available from the keyboard hub, but it is at least odd that there seems not to be enough for a thumb drive.

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