The oldest character, Gregor Relak, is currently around 110 years of age.
He is 113 right now.
Age was not introduced until some time around 2005-6, but I think characters created before then were given ages based on their creation date. Not sure about that last, though.
Here's what we know about age. Characters were indeed given ages based on the normal aging formula (I worked it out once, but I can't really remember how long it is for a year I think 28 days or so). Stuart's character Doc was exactly 3 days older than Gregor for a really long time, and it's probable that this was exactly how much older he was. Aging is sped up by wounds and positions of power to varying degrees.
As Delvin said a simple wound can be serious business as you get older, it's how Gregor lost the Dukeship of Westmoor city. A light wound ended up putting him out of commission for 10 or 11 days. It's a record for me anyways.
Aside: Stu's player ID was 10, my own is 34, Tom's is 35 (Which I find amusing to no end). Stu and I agreed that it was likely he managed to keep the original account from when BM spun off from SM.
