Web Start Error dialog, "Bad Installation.Error Invoking Java VM(execv) " is displayed many times during Javaws automation test.

Tested build:6u5 b04 PIT
OS:Vista,XP

Till yesterday this was happening only on Vista for every 3-4 tests .On XP the test was executing fine.
From today morning this error started coming in XP also,for the first test iteslf.
Launching control panel manually gives "Could Not find Main Class " Error both in Vista and XP today.
Bundle downloading is not happening unless we use the workaround of kernelDownloadUrl in registry.There seems to be some problem with hosting of the bundles now.

With the workaround of adding the key in registry
HKLM\Software\JavaSoft\KernelDownloadUrl with
value
http://sqindia.india.sun.com/disk17/deployment/PIT_6UR/2007-09-12/kernel_bundles
- the error is not coming both in XP and Vista.
Even with the workaround ,Bad Installation error dialog is coming in Vista.
This is an automation blocker.attaching the screen shot.(vista_badinstallation.JPG)
Reproducible with 6u5b05 PIT also.
Reproducible with 6u5b05PIT in IEC during automation in Vista