Please post the full stack trace and the environment (OS and JDK versions).
Sorry Alejandro but, after more accurate checks, it looks like it was my mistake.
In fact, I forgot to attach the source code in the src folder to the jBPM.jar file during the installation, and now that I've done it, it looks like it works.
Thus, the first consequence for this installation error is the impossibility of XML validation, even though the examples begin their tests.
Thank you for having replied,
what you mean attach the source code? i got the sampe problem with you.. can you explain it to me... how you fixed it....?