PRAM battery dead or alive?

Hi,

My two-year-old PowerBook G4 Titanium 1GHz DVI had a few nasty cases of date/time amnesia recently. I did some unorthodox things to cause this, but I am not sure whether this is normal behaviour for a PB, or whether a faulty PRAM battery and/or PMU is also to blame.

Case 1: PB was asleep, I exchanged the main battery -> involuntary shutdown

Case 2: PB was asleep, AC powersupply was disconnected, left like this overnight -> main battery ran out -> involuntary shutdown

I've read somewhere that iBooks only have a capacitor, not a battery on the motherboard, but PowerBooks have one. What's the use of it if it can't handle situations like these?

For case 1, the apple website says that it is entirely my fault : http://docs.info.apple.com/article.html?artnum=106216

For case 2, shouldn't there be a safety-mechanism somehere which shuts the system down before all power is gone from everywhere?

Do you think that a new PRAM battery would help?

TIA,
Karen

PS: Does anyone know a reliable UK supplier for these things? --
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