As I thought. Not IDE 1.0+ compatible.
You need to either:
. Use a pre-1.0 version of the IDE.
. Find a newer version of the library, or contact the author and get them to update it.
. Update it yourself.
If you want to update it yourself, there are a number of things you need to do.
. See point 2 at http://arduino.cc/forum/index.php/topic,97455.0.html
. The library makes use of NewSoftSerial. You will need to replace all occurrences of NewSoftSerial with SoftwareSerial.
. Replace all:
. There may be other things too.