Environment of testing: 32bit winxp, 8 nightly bundle #590

Steps to reproduce:

- load test app http://rehte.cn.oracle.com:8080/wshost/new_framework/new_framework/tests/plugin/customprogressbar/html/signed/testMixedCodeToRun2.html
The custom progress jar is unsigned, and app jar is signed.
- Click Run on unsigned security dialog
- Click Run on self signed security dialog
- If there is no mixed code dialog, and app runs, bug is reproduced.

signed custom progress with unsigned app scenario works well. mixed code dialog can be seen. For example, http://rehte.cn.oracle.com:8080/wshost/new_framework/new_framework/tests/plugin/customprogressbar/html/signed/testMixedCodeToRun.html

Source code location:
http://rehte.cn.oracle.com:8080/wshost/new_framework/new_framework/tests/plugin/customprogressbar/src/