I'm guessing that it is probably not unusual as some bunnies as prodigious wax producers, especially lops. You need to get it out of there however and the sooner the better. Use a q-tip and just swab the area gently. Your bunny won't like it so you may want to wrap him up in a towel first so he can't scratch you or hurt himself trying to get away. I know the vets over here have a solution they put in the buns ears first to help soften up the wax.
Do be very careful in attempting to get that out of there. Bunnies ears are very delicate. Or take him to you bunny-specialist vet. Good luck.