I would presume that the odour is normal, especially as he is a male. I presume this as my male guinea pigs have a strong odour too. It is similar to that of a Tom cat (not in smell but in it's nature). A male cat will 'spray' its territory and, not that Guinea pigs and rabbits are territorial animals but, they will also scent their homes and possesions. (even favourite people.. one of my prize boars Kenny will always rub his scent all over my sister when she visits). So in it's nature I would say that it is perfectly normal. Unfortunately, I have never kept male rabbits only ever females but, they also have their own particular scent.. although I should imagine less pungent to that of the male.