r.mapcalc, floating point

[grass at genie.saff.utah.edu]

Help please,
here is the simple r.mapcalc I'd like to run:
	snoele12_37 = 228*exp(1.2,elevation/1000)
It runs, however the 'elevation/1000' doesn't seem to hold a floating
point during the evaluation.  Therefore the only values in my map are 228,
274 which equals 228*exp(1.2,1) and 328 which equals 228*exp(1.2,2).  I
would really like all values in between.  Any suggestions?

Jason Carey
Snow Hydrology
University of Utah