on windows, the regutil call create and append to a log file in the $TEMP directory:
java_install_reg.log.
This was put in to help debug broken installs.
When starting plugin or webstart, a call is made by the Config initialization tto PlatformSpecificUtils.getPublicJres().
(Plugin initialization also calls UpdateCheck.shouldPromptForAutoCheck())
These two calls are instrumented alowindows ng with the other calls in regutils.
This instrumentation should be removed so starting plugin or webstart will not create or append to this file.

further, the static initialization of windows PlatformSpecificUtils loads regutils.dll.
so this is always loaded when starting webstart.
but there is nothing from regutils needed by webstart. It should not ever access PlatformSpecificUtils.
Curently, PlatformSpecificUtils is only accessed via the Config initializations call to
PluginJavaInfo.initialize() (which calls the above PlatformSpecificUtils.getPublicJres(), but there is no reason for a webstart app to initialize PluginJavaInfo.