I succesfully installed 10.5.5 on my 901 after some trial and error, seems to be very stable, I'm very happy! (no sound/ethernet of course)
I have a 2Gb SD card inserted in the reader slot for additional storage.
I've added the Kext to sleep the machine when the lid closes. When the device comes out of sleep I get the "Device Removal" warning message (like I would if I pulled a pen drive out of my iMac without unmounting first).
If I remember to unmount the SD card everythings OK and the card automounts when the machine wakes up, but is there a way to stop the warning message? i.e close the lid without having to unmount?
I make sure nothing is accessing the SD card before closing the lid.