Bonding:  Rabbits Need Friends Too!
http://www.adoptarabbit.com/articles/packet/bonding.html


Rabbits, like people, enjoy the company of others. Companionship
helps to fill the hours while owners are away at work or out of
the home. A bored rabbit may get into more mischief than a rabbit
focusing attention on a companion.


Rabbit to Rabbit

The first thing you will need to do is find a companion for your
rabbit. Male with female pairs seem to work the best for
compatibility but female to female can also work. Male rabbits
seldom get along with other male rabbits unless started as
littermates. All rabbits should be spayed or neutered before
introductions begin.

Start the bonding process before the rabbits are allowed to
interact. Place the rabbits in separate cages in sight of each
other. Let them get used to the presence of another rabbit for
several days before actually letting them meet.

Rabbit introductions should be done in a neutral territory. This
is a place the existing rabbit has never entered. The room should
be large enough for the rabbits to move around yet small enough
so the rabbits can interact.

Newly introduced rabbits may go beyond hand shaking; they may
fight. You should have a water spray bottle and towels handy to
break up any fighting. Do not break up fighting with your bare
hands, as the rabbit may not differentiate whom he is attacking.
Discontinue bonding session before bites result in injury.
Rabbits may chase and show dominance behavior (mounting) during
the introductions. These are normal activities to determine which
rabbit will be the leader.

It is very rare for the rabbits to start grooming or lying
together during the first bonding session. The bonding should be
limited to 20-30 minutes the first few sessions. If all is going
well you can extend the time spent together and increase the
space. Some bondings may take a few days and others may take
weeks or even months. One or two litter boxes should be available
in the bonding space. The rabbits may mark territory with fecal
pellets at first but once the leader is determined this should
lessen or subside.

Once the rabbits are comfortable with each other and no fighting
occurs you may want to let them explore one another's cages. Keep
them separated at night until you are sure they will not fight.
When both rabbits are comfortable with each other they can be
kept in the same cage and your bonding is complete. The rabbits
may occasionally show dominance behavior even though they are
successfully bonded.