Mounting images on 10.4.5

I was trying to mount a disk image on my 10.4.5 as usual:

[ambs@Diabelli Desktop]$ hdiutil attach lilypond-2.6.5-1.dmg
load_hdi: timed out waiting for driver to load

but as you suspect, that last line is not usual. It is repeated a lot of times, and finally does timeout. Meanwhile, googled around but didn't find a solution. A friend helped me solving this with:

sudo kextunload -c com.apple.AppleDiskImageController
sudo kextload -b com.apple.AppleDiskImageController

It works. I can mount the image after this unload/load procedure. The problem is that if I reboot, I need to do this all again. I tried to update kext caches but it didn't work (or I didn't update the correct ones). If you had this problem, or if you know how to help me, please let me know.

If I insert a flash disk nothing occurs. Unfortunately I didn't have much time to debug it yet. To unload/load the kernel module doesn't solve this.

I am desesperating.