Xin, I have no idea if this is what you are after, but we use a program called
CORPSCON to convert lat/long to UTM or other system. GRASS m.proj and v.proj
have not worked for me in the past. At least not for OKLAHOMA. If you are
interested in finding out more about CORPSCON, either call of e-mail me for
info.
regards,
Chris D Garvin
Ft Sill, OK (405) 442-3314/6174