Thanks Erel, I pieced together pieces of information from the forum and Google.
It was to do with the .so file (which I had to add to the project) but mainly the problem was that although the file was called libABC.so I only needed the "ABC" part in the loadlibrary command.
My library is now working. Thanks for the update about 1.7, Ill change my target version back to 1.7