SUGGESTED FIX

http://sa.sfbay.sun.com/projects/deployment_data/6u10/6635826.0
testcase: http://web-east.east.sun.com/deployment/www/tests/1.6.0_10/6635826/
                                     

EVALUATION

Attempting to make the new plug-in run on top of JDK 1.4.2 (on
Windows) required the following changes:

  - Switched to -target 1.4 for all plugin classes

  - Avoiding the direct use of System.getenv(), which was broken on
    JDK versions before 5

  - Guarded certain System.loadLibrary() and load() calls due to less
    robust System.load() implementation on 1.4.2

  - Refactored progress listener support and guarded against lack of
    it on 1.4.2

  - Guarded against lack of sun.net.www.ParseUtil.encodePath(String,
    boolean) on older 1.4.2 versions

  - Failed gracefully if the DeployCacheHandler, proxy and cookie
    initialization fail due to lack of dependent classes

  - Dealt with lack of Thread.getState() on JDK 1.4.2

  - Loaded regutils DLL early on Windows

Also added better support for debugging bootstrapping issues in the
new plug-in.

Applets now run on top of the new plug-in on JDK 1.4.2 on Windows.
Because there was no XEmbed support even in the AWT MToolkit on
Unix/X11 platforms in the JDK 1.4.2 release, it is infeasible to make
the new plug-in run on top of JDK 1.4.2 on X11 platforms.

Related bugs 6611381 and 6636067 are still to be resolved for more
complete functionality when running on 1.4.2.