NoClassDefFound error is a nebulous error and is often hiding a more serious issue. It is not the same as ClassNotFoundException (which is thrown when the class is just plain not there).
NoClassDefFound may indicate the class is not there, as the javadocs indicate, but it is typically thrown when, after the classloader has loaded the bytes for the class and calls “defineClass” on them. Also carefully check your full stack trace for other clues or possible “cause” Exceptions (though your particular backtrace shows none).
The first place to look when you get a NoClassDefFoundError is in the static bits of your class i.e. any initialization that takes place during the defining of the class. If this fails it will throw a NoClassDefFoundError – it’s supposed to throw an ExceptionInInitializerError and indicate the details of the problem but in my experience, these are rare. It will only do the ExceptionInInitializerError the first time it tries to define the class, after that it will just throw NoClassDefFound. So look at earlier logs.
I would thus suggest looking at the code in that HibernateTransactionInterceptor line and seeing what it is requiring. It seems that it is unable to define the class SpringFactory. So maybe check the initialization code in that class, that might help. If you can debug it, stop it at the last line above (17) and debug into so you can try find the exact line that is causing the exception. Also check higher up in the log, if you very lucky there might be an ExceptionInInitializerError.