Motorola MPx200 question

Here's a question for you. I have a MPx200 that I got
off of eBay a while ago. The phone works great all
except for the battery life. I'm noticing that I get
about six hours of usage out of the battery.

According to the date code on the battery, it was
manufactured on 01/29/2004, so the battery isn't
really that old timewise, but like I said, I don't
know the history of the battery, so it could possibly
have gone bad (leaving it in a hot car, what have you.

I'm going to charge the battery till the phone says
it's full, then pull it and take a multimeter to it
and see if I'm getting the full 3.6v out of it.

My first instinct is to say that the battery
isn't holding a charge for whatever reason, and to
replace it, but I thought I'd ask for a second opinion.

Thanks,

Chris
acadia@peacefulhaven.net