iMac, MacOSX and Sleep


I have an iMac DV Indigo with 128Mb PC100 memory (got the boring bit out of the way)
I had no problems installing MacOSX on the machine and everything works fine, Internet, sound, and programs (I was happy to see that Apple has carbonised Appleworks, which I was not expecting)
The only problem I have encountered is that I cannot put my iMac to sleep. I select Sleep from the menu bar and nothing happens. I can shutdown, reboot etc... but no sleep :/ I have nothing plugged into my iMac, except keyboard, mouse, modem cable and an Ethernet cable which is exactly the same as I had in MacOS 9.0.4
I found the sleep feature the most useful think in MacOS 9.0.4 because I did not have to wait for the OS to boot.

Any ideas why the sleep does not work ?

The Apple have a big trouble with USB devices...In future, with G5 platform, this problem will be solved, but now, you don't have nothing to put your machine to sleep... My own don't sleep too.... So, VIVA STEVE JOBS!!!
Hay your not alone. I have a G3 tower and i cant put it to sleep either. But it will fall a sleep if you set the settings and let the time go by.

I have the same sleep problem with my Cube.
It's really annoying, couse I want to use my cube as an alarm clock.
It is quiet, but the hard drive does produce a whining sound when everything else is off.
I wish there was a way to put the disk to sleep (as in OS9).
Same problem here. G4/500SP/256, no sleep either manually or from energy saver preference. The screen powers down fine, but selecting "Sleep" from the Special menu does nothing.
Sleep is still in progress. As mentioned in the help files, some machines will not yet sleep. This should not be a problem in Mac OS X version 1.0. It is not an issue with your hardware.

Same here, my G3 b/w wont sleep.
Hey wasn't there talk of another feature like sleep
called "Dream"?
Where a mac could be in sleep mode but process stuff like 3D rendering or movie encoding?