[GRASS5] Using fp

[Gualter Barbas Baptista]

I'm having some problems with the map operations because GRASS insists 
in truncating the cell values to integers.
I saw in some older documents that fp support would be integrated in 
GRASS5, but then I didn't find anything on how to use it (since most of 
the documents/tutorials refer to version 4.x).
Is this really implemented now? How can I convert my maps and/or make 
r.mapcalc operate with fp numbers?

Thanks,

Gualter