I rehab biters and the following suggestions might help.  Under no
circumstances flick you ferret on the nose.  Most people will tell you
to scruff, scruff and drag and timeouts.  All of these do work.  I don't
work with any kind of punishment.
 
I work strictly with treats and gloves if needed.  I use both olive oil
and ferretvite.  I reach in the cage give the ferret a treat and pick him
up moving him from one place to another.  I'll reach in and just pet him
while giving him a treat.  This gets the ferret used to being handled and
associates you hands with good things.
 
If he is a vicious biter and you don't have time to give him a treat,
wear gloves.
 
I have a house full of biters, some have been abused or neglected.  While
they aren't suitable to take out in public, they don't bite us.
 
KG
[Posted in FML issue 5227]