R help - Oct 2011 - gvisGeoChart not recognizing US states as regions

I'm having trouble using gvisGeoChart with region fills. I would like to 
fill a map of the U.S. by state. The documentation says it can be of the 
form "US-NJ" or "New Jersey", but I tried both and neither
works for me.
When I tried the latter the country of Georgia is filled, so at least 
it's doing something. Am I forgetting to set something important? Here 
is a code sample:

require(googleVis)

data=read.csv("states_w_prob.csv")

GeoC=gvisGeoChart(data,locationvar="Name",numvar="prob",options=list(dataMode="regions"))

plot(GeoC)

(locationvar can be "Name" or "code")


And the first few rows of the csv file:
Name 	state 	Lat 	Long 	code 	MLAT 	prob
Alaska 	AK 	61.385 	-152.268 	US-AK 	67.16471 	NA
Alabama 	AL 	32.799 	-86.8073 	US-AL 	40.19146 	0.177872
Arkansas 	AR 	34.9513 	-92.3809 	US-AR 	42.68162 	0.215224


Thanks in advance for any insight.

Nicole

	[[alternative HTML version deleted]]