Posted By Nibbles_NZ on 05/21/2010 08:08 PM
Is this behavior due to his maturing?
Short answer: YEP!
Hopefully you were able to put the litterbox back. It sounds like his aggression was definitely only due to your other bunny’s scent, and yes his poos are going to be smelly– since he can put a thin little skunky smelling goop over his poos (that’s what those lovely anal glands are for) Yucky.
Sooooo…..I bet June 17th can’t come soon enough now. 
In the meantime, give him some phonebooks to tear up. And obviously now you’ve figured out that you may need to wash your hands after touching Bella. Does she stay in the same room with him normally? IF so, you could also use a toy bunny or just stuff a sock and then get Bella’s scent on it by brushing Bella, and then rubbing the fur all over the toy or stuffed sock and let him work out his…eh hem..
…frustration.
If he can work out some of his raging hormones, it may make him easier to deal while you wait for June 17th.
Good Luck and Hang in there.