Javaws SSV autodownload tests fail with 1.4.2 but pass with 1.4.1

Systme => x86-RHEL3.0AS
Browser => Firefox 2.0
JDK => 1.5.0_12-ea-b01 (installed using jdk.rpm bundle)

Child Workspace => /net/jqa.ireland/jqa6/dtf/dtf_ws/suites/deployment_tiger_UR1_int_ws_current/deployment
The above workspace is synced once a week with the parent workspace.
Parent Workspace => /net/sqe1.sfbay/quality1/deployment1/deployment_tiger_UR1_int_ws

Results URL => http://jqa.ireland/results/1.5.0_12/Build01/deployment/javaws/x86-RHEL3.0AS-FF2.0/main_run/

Unexpected Failures:
JRESSV005_001_1.4.2
JRESSV006_001_1.4.2
JRESSV007_001_1.4.2
JRESSV008_001_1.4.2
JRESSV008_003_1.4.2

Reproducibility => 100%

To reproduce please do the following:

1. Install jdk 1.5.0_12-ea-b01
2. Run the following testcase
"javaws http://nicole1.sfbay.sun.com:8080/JavawsTigerIntegTest/ssv/test_signed_1.4.2.jnlp"

It fails with "Launch File Error - Unable to launch SSV using 1.4.2 signed".