arc and lithium AA

My arc appears to have died it was working friday on sat I attached it to the zip of my caving suit (its a 3rd backup) went to check it and it didnt turn on!!
Tried a new battery that didn't help.
I have been using a lithium aa (1.5V) not a high voltage 1440.
For the past couple of weeks it has been acting odd. Its been dimming after a short period thought usually turning off and back on has fixed it.
so did the lithium aa kill it?
If not other ideas? I have checked the threads and the tube no luck.
If it is dead what should i replace it with that costs < $30 including postage to the uk?
how much bigger is http://www.dealextreme.com/details.dx/sku.6121
how much bigger would a single cr123 be for keychain / heavy duty zip use ?

I don't think a lithium AA would kill. It I've been using a lithium AA in my Arc Premium for over a year now with no problem.

I didnt think it would either, there has to be regulation so any ideas why it died ?
I miss it already :shakehead

I dont own one but I have seen a post from Peter Gransee (Mr Arc) that said that the 1.5v aa lithiums are fine to use. I would suggest e-mail to Arc to see if he might suggest anything. Also check out the arc forum on CPF. for help.
Jerry