Creating lib file from java jar using mingw/gcj

Question

I am trying to convert jar file to native lib file using mingw-gcj under windows platform but it is throwing me the error as

 C:\testDir\libs>gcj -o glassfish-embedded-all-3.1-SNAPSHOT.lib glassfish-embedde
d-all-3.1-SNAPSHOT.jar
com/sun/codemodel/JAnonymousClass.java: In class 'com.sun.codemodel.JAnonymousCl
ass':
com/sun/codemodel/JAnonymousClass.java: In constructor '(com.sun.codemodel.JClas
s,com.sun.codemodel.JCodeModel)':
In file included from com/sun/codemodel/CodeWriter.java:15,
                 from <built-in>:3:
com/sun/codemodel/JAnonymousClass.java:21: error: verification failed at PC=3: c
onstant pool index out of range
com/sun/codemodel/JAnonymousClass.java:21: confused by earlier errors, bailing o
ut

Is it related to some java 1.6 issue or bug in gcj /