Problems extracting model.matrix from multinom fit (nnet library)

[Frederico Zanqueta Poleto <fred@poleto.com>]

Dear All,

I have a fit from multinom (nnet library).

When I try the command model.matrix(fit) in S-Plus 2000 or in R 1.7.1, 
everything is ok. But in S-Plus 6.1 I receive:
Problem in formula$terms: function "$" not defined for non-vector class 
"multinom"
Use traceback() to see the call stack

Anybody know what is happening?

Best wishes,

--
Frederico Zanqueta Poleto
fred@poleto.com - ICQ# 4129787