facing issue while migration from jdk 1.5 to jdk1.6
Recently we migrated from jdk 1.5 to jdk 1.6. We are using an API of a jar which is compiled in jdk 1.2. The code inside the jar is not with us. But after shifting jdk 1.6 it gives an exception. This exception is user defined exception. So, getting no clue from it. I thought maybe the issue with sqljdbc jar. As jdk 1.6 requires sqljdbc4 and jdk 1.2 require sqljdbc jar. So, what might be the issue? 
facing issue while migration from jdk 1.5 to jdk1.6
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Recently we migrated from jdk 1.5 to jdk 1.6. We are using an API of a jar which is compiled in jdk 1.2. The code inside the jar is not with us. But after shifting jdk 1.6 it gives an exception. This exception is user defined exception. So, getting no clue from it. I thought maybe the issue with sqljdbc jar. As jdk 1.6 requires sqljdbc4 and jdk 1.2 require sqljdbc jar. So, what might be the issue? 