FULL PRODUCT VERSION :
java version "1.7.0_55"
Java(TM) SE Runtime Environment (build 1.7.0_55-b13)
Java HotSpot(TM) 64-Bit Server VM (build 24.55-b03, mixed mode)

A DESCRIPTION OF THE PROBLEM :
The problem is described here : https://community.oracle.com/thread/3550362 
and there: http://stackoverflow.com/questions/23217131/java-7-update-55-jacorb-error-when-running-via-webstart
It seems to happen with openorb, corb, Orbacus, ...
Someone may have already opened a bug to Java for this (Review ID: JI-9011898) but not able to find it in http://bugs.java.com/.

I've just updated to the latest java 7 release (update 55) and am now unable to launch my webstart application.

This application works fine on java 7 update 51.

The application also works fine if launched outside of webstart using update 55.

Any idea what change in this latest update would cause this? and how to resolve it?
 

Many Thanks

REGRESSION.  Last worked in version 7u51

ADDITIONAL REGRESSION INFORMATION: 
java version "1.7.0_51"
Java(TM) SE Runtime Environment (build 1.7.0_51-b13)
Java HotSpot(TM) 64-Bit Server VM (build 24.51-b03, mixed mode)

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
javaws.exe my.jnlp

ACTUAL -
An exception is thrown.

ERROR MESSAGES/STACK TRACES THAT OCCUR :
The Exception i'm getting is:

org.omg.CORBA.INITIALIZE: can't instantiate default ORB implementation org.jacorb.orb.ORBSingleton vmcid: 0x0 minor code: 0 completed: No

  at org.omg.CORBA.ORB.create_impl_with_systemclassloader(Unknown Source)

  at org.omg.CORBA.ORB.init(Unknown Source)

  at org.jacorb.orb.CDRInputStream.<init>(CDRInputStream.java:186)

  at org.jacorb.orb.etf.ProfileBase.initFromProfileData(ProfileBase.java:252)

  at org.jacorb.orb.etf.ProfileBase.demarshal(ProfileBase.java:172)

  at org.jacorb.orb.etf.FactoriesBase.demarshal_profile(FactoriesBase.java:124)

  at org.jacorb.orb.ParsedIOR.decode(ParsedIOR.java:235)

  at org.jacorb.orb.ParsedIOR.parse_stringified_ior(ParsedIOR.java:460)

  at org.jacorb.orb.ParsedIOR.parse(ParsedIOR.java:375)

  at org.jacorb.orb.ParsedIOR.<init>(ParsedIOR.java:192)

  at org.jacorb.orb.ORB.string_to_object(ORB.java:1824)

 

Caused by: java.lang.ClassNotFoundException: org.jacorb.orb.ORBSingleton

  at java.net.URLClassLoader$1.run(Unknown Source)

  at java.net.URLClassLoader$1.run(Unknown Source)

  at java.security.AccessController.doPrivileged(Native Method)

  at java.net.URLClassLoader.findClass(Unknown Source)

  at java.lang.ClassLoader.loadClass(Unknown Source)

  at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)

  at java.lang.ClassLoader.loadClass(Unknown Source)

  at java.lang.Class.forName0(Native Method)

  at java.lang.Class.forName(Unknown Source)

  ... 56 more

REPRODUCIBILITY :
This bug can be reproduced always.

CUSTOMER SUBMITTED WORKAROUND :
The only workaround I see is to go back to update 51.