R help - Aug 2005 - tkinsert matrix - how to display a matrix with tcltk

dear list,
I have problems with tkinsert
I need to display a matrix as a result of my function, but when I use  
tkinsert(txt, "end", myMatrix, sep="\n") I simply obtain a
string.

I do:

n<-tclVar()
tclObj(n)<-matrix(data, ncol=lenght)
tkinsert(txt, "end", tclvalue(n), sep="\n")

any hints?

thank you in advance,
simone gabbriellini