This bug seems to be specific to Vista.
If one specifies the -Xbootclasspath argument in the Java Control Panel with some jar filenames containing the "-" character, portion of the beginning of the argument will be truncated.

For example, if the -Xbootclasspath is as follows:
-Xbootclasspath/a:d:\testjar\javafxrt.jar;d:\testjar\jmc.jar;d:\testjar\Decora-OGL.jar;d:\testjar\Decora-D3D.jar;d:\testjar\Decora-HW.jar;d:\testjar\gluegen-rt.jar;d:\testjar\jogl.jar;d:\testjar\Decora-SSE.jar;d:\testjar\PathAnimation.jar

The commandline of the launched client jvm will be as follows:
"D:\Program Files\Java\jre6\bin\java.exe" -D__jvm_launched=3783192382 "-Xbootclasspath/a:D:\\PROGRA~1\\Java\\jre6\\lib\\deploy.jar;D:\\PROGRA~1\\Java\\jre6\\lib\\javaws.jar;D:\\PROGRA~1\\Java\\jre6\\lib\\plugin.jar" "-Djava.class.path=D:\\PROGRA~1\\Java\\jre6\\classes" "-D3D.jar;d:\\testjar\\Decora-HW.jar;d:\\testjar\\gluegen-rt.jar;d:\\testjar\\jogl.jar;d:\\testjar\\Decora-SSE.jar;d:\\testjar\\PathAnimation.jar" "-Dsun.plugin2.jvm.args=-D__jvm_launched=3783192382 \"-Xbootclasspath/a:D:\\\\PROGRA~1\\\\Java\\\\jre6\\\\lib\\\\deploy.jar;D:\\\\PROGRA~1\\\\Java\\\\jre6\\\\lib\\\\javaws.jar;D:\\\\PROGRA~1\\\\Java\\\\jre6\\\\lib\\\\plugin.jar\" \"-Djava.class.path=D:\\\\PROGRA~1\\\\Java\\\\jre6\\\\classes\" --- \"-D3D.jar;d:\\\\testjar\\\\Decora-HW.jar;d:\\\\testjar\\\\gluegen-rt.jar;d:\\\\testjar\\\\jogl.jar;d:\\\\testjar\\\\Decora-SSE.jar;d:\\\\testjar\\\\PathAnimation.jar\" --" sun.plugin2.main.client.PluginMain write_pipe_name=jpi2_pid776_pipe6,read_pipe_name=jpi2_pid776_pipe5

Note that after the "---", it starts with "-D3D.jar" which is the truncated name of Decora-D3D.jar.
The expected behavior is that the entire -Xbootclasspath string as entered in the java control panel should be following the "---".