Login as root/admin. Create a non-admin user
Install JDK 1.4.2_12. Install TZupdater v1.1.0 B04 tool on Win XP Home x86.
Log out as admin/ login as non-admin user. Try to run the update tool.

See messages below.Windows messages are unclear and are different for both public and private jre's. Solaris messages very clear compared to it.

Windows Private jre:
C:\andy\tzupdater-1.1.0-2007c\tzupdater-1.1.0-2007c>/andy/jdk/jre/bin/java -jar
tzupdater.jar -u
Can't rename C:\andy\jdk\jre\lib\zi to C:\andy\jdk\jre\lib\zi.tzdata2006a.

Windows Public jre:
C:\andy\tzupdater-1.1.0-2007c\tzupdater-1.1.0-2007c>java -jar tzupdater.jar -u
Can't create directory C:\Program Files\Java\j2re1.4.2_12\lib\zi.tzdata2007c\Afr
ica.

Solaris:
$ $JAVA_HOME/bin/java -jar tzupdater.jar -f -v
java.home: /export/home/JDKS/USDST/j2re1.4.0_04
java.vendor: Sun Microsystems Inc.
java.version: 1.4.0_04
JRE time zone data version: tzdata2006n
Embedded time zone data version: tzdata2006n
/export/home/JDKS/USDST/j2re1.4.0_04/lib is not writable.