hi guys, this is my error when i was try test Lesson 4: Mote-PC serial communication and SerialForwarder. how to solve this error. Administrator at spannlab /opt/tinyos-2.x/apps/tests/TestSerial $ make micaz mkdir -p build/micaz javac *.java /bin/sh: javac: command not found make: *** [TestSerial.class] Error 127