According to the official Opeth website's biography Axe turned 30 yesterday. So a little bit late, but better late than never, I guess: Grattis som Fan Martin!!!
Who says it's Erik's Birthday too? Has Erik been with Axe from his birth on? Or has he shown up at some later date? If they're two persons, they don't necessarily have the same birthday... This said: Happy Birthday, Axe! Here's to you:
Happy BDay Axe! I believe you're the youngest of all the Opeth dudes. Hope you had an ass-kicking birthday!