Caused by: java.lang.SecurityException: class "oracle.apps.fnd.common.Version"'s signer information does not match signer information of other classes in the same package

Oracle R12 application and getting following error when trying to launch General Ledger Account Hierarchy Manager
Java Plug-in 1.6.0_07
Using JRE version 1.6.0_07 Java HotSpot(TM) Client VM
User home directory = C:\Documents and Settings\Administrator
---
c: clear console window
f: finalize objects on finalization queue
g: garbage collect
h: display this help message
l: dump classloader list
m: print memory usage
o: trigger logging
p: reload proxy configuration
q: hide console
r: reload policy configuration
s: dump system and deployment properties
t: dump thread list
v: dump thread stack
x: clear classloader cache
0-5: set trace level to
----
proxyHost=null
proxyPort=0
connectMode=HTTP, native.
Forms Applet version is : 10.1.2.3
java.lang.ExceptionInInitializerError
at oracle.apps.fnd.tcf.ClientDispatcher.initServer(Cl ientDispatcher.java:381)
at oracle.apps.fnd.tcf.ClientDispatcher.( ClientDispatcher.java:216)
at oracle.apps.fnd.tcf.ClientDispatcher.( ClientDispatcher.java:193)
at oracle.apps.gl.jahe.javaui.client.Jahe.connectDispatcher(J ahe.java:1384)
at oracle.apps.gl.jahe.javaui.client.Jahe.jbInit(Jahe.java:10 46)
at oracle.apps.gl.jahe.javaui.client.Jahe.jump(Jahe.java:863)
at oracle.apps.gl.jahe.javaui.client.Jahe.start(Jahe.java:759 )
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.SecurityException: class "oracle.apps.fnd.common.Version"'s signer information does not match signer information of other classes in the same package
at java.lang.ClassLoader.checkCerts(Unknown Source)
at java.lang.ClassLoader.preDefineClass(Unknown Source)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknow n Source)
at java.net.URLClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.access$000(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)

Solution:
You can try the following:
1. Run Adadmin and regenerate all the jar files with FORCE option.
This can be done as per the steps below:
1.1. Run adadmin
a)select AD administration main menu option as 1) generate applications file menu
b) select generate applications files option as 4)generate product jar files
When asked for the option,
Do you wish to force regeneration of all jar files? [No] ?
Give Yes as the answer.
This will force all the jars to be rebuilt.
1.2 Once jar rebuild process is over, do the following to verify whether jars have been rebuilt successfully or not.
a. cd $FND_TOP/java/jar
b. ls -lrt
1.3 Verify, that the timestamps are the latest and reflect the jar rebuilt timing.
2. Clear java/jre cache on client PC.
3. Bounce Apache.
4. Retest the problem by logging out and logging back in.