$ rpm -q java-1.6.0-openjdk
(IIRC happens also in F-14 but cannot verify that right now)
$ javaws http://portecle.sourceforge.net/webstart/portecle.jnlp
As expected, javaws prompts the user to accept the certificate this web start app is signed with because it cannot be verified (it's a self signed one), but while doing it, it shows the wrong publisher.
This app contains two jars: portecle.jar which is the main jar and signed with my key (Ville Skyttä), and bcprov.jar which is signed with my key as well as the Bouncy Castle one. javaws should show "Publisher: Ville Skyttä" in the initial certificate acceptance prompt, but it shows "Publisher: The Legion of the Bouncy Castle".
However, "More information..." -> "Certificate Details" shows my certificate as it should.
javaws from both Oracle's and IBM's JRE's show the correct publisher in the initial acceptance prompt.
I'm being told this was part of the larger problem - see bug #677332 - and should be fixed in the latest Fedora openjdk packages. I'm seeing correct publisher with java-1.6.0-openjdk-22.214.171.124-126.96.36.199.fc13.
I no longer have a F-13 box to test with, but the correct publisher is shown with 188.8.131.52-184.108.40.206.fc14.x86_64 on F-14.
Thanks, I'm making this public and closing.