When debugging an application that involves a framework: If you debug into the framework code and the code and functions don’t match up in the debugger. You probably have a dependency issue. This is quite possibly caused by a sub-component that uses the framework you’re using, but it’s using the wrong framework version. When that happens the wrong framework version may be used at runtime.
Also to note: When using the WicketStuff library, the newer libraries have an artifiactId of wicketstuff-*. If you are using a wicketstuff component without the wicketstuff- prefix, then it will limit you to using 1.4.2.