Your PC wont pick up the PSP's memory stick as a drive when you connect it with the USB cable?
Hrms.....
I'll see if I can find anything about this.
Edit: A few questions.
Did the PSP connect to the Vista PC before you moved to 3.03oe-c?
Have you/can you try connecting it to another (windows XP) PC and see if that works?
When you plugged it in and put the PSP into USB mode, did windows say anything about installing something like 'PSP type A' and then ask for drivers? Or do anything at all?
Sometimes you see it setting up the device but then it doesnt appear in my computer.
You could just try plugging it in and unplugging it a few times, try another USB port on your PC or even restarting the PC and trying again.
I found
THIS, but I would save that for a last resort.
Just trying to narrow it down to a vista issue or a custom firmware issue.