There seems to be some failure during DirectionSService
I tried calling the API between two cities in USA and couldnt get it
to work.
Infact, even the showcase application gwt-maps3 doesn't seem to show
the directions anymore...
I found some exception in the stacktrace..it may help.
'Unknown property <provideTripAlternatives>' in
http://maps.gstatic.com/intl/en_us/mapfiles/api-3/0/40/
Other than that , it is an easy library to use. Thanks for this.