Hard disk recognised is very very strange way

Hi
I have not been able to use my external FAT32 USB hard drive since the 10.4.10 update. Many other also suffered this. Here it is in detail:

External Hard drive not recognized, speaker noise, because UPDATE?

However, now I just copied my internal drive (on my macbook) to an external HFS+ drive, and when I boot from that drive now, I can access my FAT32 drive! It can see it fine.

Then, even more strange, if I shutdown, and then start up from my internal drive, it can also see my FAT32 drive!! BUT, inly for the first time. I can use it, everything is normal. But, if I dismount it, then that's it. If I turn the drive on again, it will not see it, not recognise it. Even if I restart my computer, it will still not see it. However, if I reboot from the external HFS+ drive, then restart again from the internal drive, again I can see the FAT32 drive. Only the first time.

To someone, this probably makes sense. Perhaps it tells you where the problem is? Could be very useful! I would really love to use this drive! The only solution on the net given, sounded very complicated and some people had big problems from it. So maybe this now indicates a simpler solution (seeing as mac seems to be doing nothing about it!)

Thank you!
Justin