For example, in JDK 7 b127 PIT bundles, the names of the bundles have b123
and the java -version has 125.
http://j2se.east.sun.com/arc/ds_build/1.7.0/nightly/2011-01-17/windows-i586/

Bundle names:
# jdk-7-fcs-bin-b123-windows-i586-17_jan_2011.exe
# jdk170.exe
# jinstall-7-fcs-bin-b123-windows-i586-17_jan_2011.cab
# jre-7-fcs-bin-b123-windows-i586-17_jan_2011-s.exe
# jre-7-fcs-bin-b123-windows-i586-17_jan_2011.exe

This needs to be fixed.