A method monitors non-faulty application traces of a computer application with the runtime environment during fault-free activities to create non-faulty runtime signatures for the computer application. Once obtained, the method stores the non-faulty runtime signatures. The method then detects a faulty application trace of the computer application and compares the faulty application trace with the non-faulty runtime signatures by comparing a call graph of the faulty application trace with call graphs of non-faulty application traces of the application signatures to identify differences between the two (e.g., fault attributes). Then the invention outputs the fault attributes to allow the user to identify a fault cause.