Rectify into LL

[Usuario de GRASS 4]

I want to convert a scanned map (x,y coordinate system) into latitud/longitude coordinate system. With the i.points (i.rectify,...) command I can convert my map into the UTM coordinate system or the State Plane coordinate system but not into latitud/longitude coordinate system.
Does anyone know how could I do this?.
I would very much appreciate any help people could offer. Thanks in advance.

Anabel Donadios
Eurogis
anabel at tilo.datsi.fi.upm.es