build tested - Mustang rc build 87 SWAT build
bundles location: /net/mizu.sfbay/usr/re/jdk6/bundles/*/latest
Tested configurations - Win XP Home/IE, Win 2000 Pro/MZ, Solaris Sparc 10/MZ

Steps to reproduce

Install JRE mustang b87 SWAT build from the above location
Invoke IE or MZ browser
Load the following MIMETYPE applet :
http://sqeweb/deployment1/deployment_mustang_int_exec_ws/deployment/tests/BATTestsuite/pluginhtml-default/Default_MimeType_160.html

The applet does not load, and you see the following exceptions :

For Internet Explorer
-----------------------
java.lang.NoClassDefFoundError: Could not initialize class java.awt.TextArea
at MimeTypes.init(MimeTypes.java:21)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)

For Mozilla
-------------
java.lang.ExceptionInInitializerError
at MimeTypes.init(MimeTypes.java:21)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.ClassCastException: javax.swing.KeyStroke cannot be cast to java.lang.Comparable
at java.util.TreeMap.compare(Unknown Source)
at java.util.TreeMap.put(Unknown Source)
at java.util.TreeSet.add(Unknown Source)
at java.awt.KeyboardFocusManager.initFocusTraversalKeysSet(Unknown Source)
at java.awt.TextArea.<clinit>(Unknown Source)
... 3 more

This is a regression from b87.