Filled contour and projection

Dear all!

Is it possible to make a plot with filled contour on a map with a 
certain projection? It is not a problem using the mapproject() together 
with contourLines() to make e.g. a stereographic plot with contour 
lines, but it seems rather impossible to use filled.contour() and 
mapproject together in the same way.

In advance, thanks for all your help!

Best Wishes
Dag Johan Steinskog