Originally Posted by chionophile
That's (probably) not beer. You generally don't keep beer in a flask and you certainly wouldn't mix it with tea. I'd guess it's something like whiskey or rum.
Edit: Although, I guess Durkon might just love beer that much. It's possible *shrug*.
In a bonus strip in War and XPs he was carrying holy beer in a flask. It was specifically stated to be beer, but I admit, I don't know.