-Go to Add/ Remove programs
-make sure that 'show updates' is checked
-locate windows update KB898715
-restart the system
-install the jre (normally , there will be no problem at this level)
-run a windows update to reinstall the removed installer update(KB898715)
If you are unable to install J2SE 1.5.0 update 4 on Win 2003 SP1, uninstalling update KB898715 may help you. Good luck.