JDK/JRE tested: JDK 6u15-b01.
OS/architecture: Windows, generic.
Reproducible: Always.
Reproducible on machine: Any windows machine.
Also reproducible on machine: Any windows machine.
Is it a Cross-platform regression: Y
[If yes] is it a new platform support: N
[If yes] Regression relative to OS version:
Is it a Regression: Y
[If yes] Regression from release/build: 6u14-b08
[If yes] Test result on FCS: Pass (also passed with 6u13-b03 & 6u14-b08)
Test run log location: Please see attached screenshots to this bug.
Steps to reproduce:

1. Remove all JDK/JRE from windows system.
2. Install JRE 6u15-b01.
3. Clear Java cache beforehand via the JCP in the Windows Control Panel or via the command line using "javaws -uninstall"
4. Attempt to run a application (JNLP) via the command line as follows:

$ javaws http://ventura.ireland.sun.com:8080/JavawsMustangIntegTest/hellojaws/BAT.jnlp

Issue is reproduced if you are prompted to download an earlier version of JRE in order to run application (See screenshot for example).

5. If one launches the same application via browser the application runs ok (see screenshots). I used default browser (which was IE for each windows box).

Test case passes with 6u13-b03 & 6u14-b08 on Solaris10, RHEL5, Windows XP, Windows 2008 & Windows Vista.

Test case fails via the command line with 6u15-b01 on Windows XP, Windows 2008 & Windows Vista. Test case passes with 6u15-b01 if run via browser.

The JWS cache was cleared prior to run the test case via the command line each time.

Please find attached screenshots & a small html file which basically show PASS-FAIL comparison for above platforms. Another test case which fails is BAT_security.jnlp

NOTE: Not all JNLP files hosted on http://ventura.ireland.sun.com:8080/JavawsMustangIntegTest fail e.g. notepad passes with 6u15-b01. So possibly it depends on nature or intention of test case.