Try putting some bedding there.  I read the suggestion from a ferret
magazine that I was going through.  The article mentioned that a ferret
wont go on his beding.
 
By babies were going under the table and the kitchen, where I couldn't
get to (I am disabled and live in a special apartment, so there is no
cabinets under the sink so people in a wheel chair can get closer).  I
have put old sheets down under the table and an old beach towel under the
sink.  It has worked beautifully.  The article suggested covering you
whole floor if you are trying to litter pan you ferrets.  I don't have
enough sheets to do that.
 
Phyllis and the Wigglies: Generosity, Grace and Joey (Joy)
In Loving Memory: Faith, Hope, Constance, Bandit and Charrity
[Posted in FML issue 4550]