Just tiny changes to enable the package to be compiled
under jdk 1.5
enum is a reserved keyword for jdk 1.5, need to be
renamed it from 4 files
.getState() conflict with Thread.getState() under jdk
1.5, need to be renamed.
thus the package can be compiled under jdk 1.5. for
complete jdk 1.5 compliant, program code may need