Reproduced it with 6u19 b03 on Vista aand XP.

Script file query_JRE_HOME.js returns Error.
Log file can be found here and it is attached in the CR.
http://sqeweb.sfbay.sun.com/deployment2/ranjitl/install-results/6u19-b03-rerun/Standalone_deployment_install_2010_03_05_17_29_15/Ken.Windows_Vista.x86/AUWith6UX-1To6UX-01/AUWith6UX-1To6UX-01.log

Failure:
# Actual: INSTALL_STATUS=0
[2010-03-06T01:35:56.21] parserVariable_19=`cscript.exe //Nologo ${DEPLOY_SHARE_HOME}/bin/query_JRE_HOME.js `
[2010-03-06T01:35:56.21] # Actual: parserVariable_19=`cscript.exe //Nologo Y:/sqenfs-1/comp/quality1/deployment2/ranjitl/deployment_6_UR_int_ws/deployment/share/bin/query_JRE_HOME.js`
[2010-03-06T01:35:56.21] Error