Set JAVA_HOME to the jdk location under which
jre/bin/client can be found.  The Makevars will be
set up properly.

For windows platforms, please set variables in 
src/Makevars.win

At present the following suffices for a default install from Sun:

PKG_CPPFLAGS=-IC:/progra~1/java/jdk1.5.0_01/include \
	-IC:/progra~1/java/jdk1.5.0_01/include/win32
PKG_LIBS=-LC:/progra~1/java/jdk1.5.0_01/jre/bin/client -ljvm