Stellina,
It looks good. It seems to be installing the server alright.
I would suggest you to download this one. http://sourceforge.net/projects/jbpm/files/jBPM%205/jbpm-5.0-Final/jbpm-5.0.0-installer-full.zip/download and to use the jbpm 5 userguide to install it. I have been using it and never had problems.
Sorry could not figure out the problem.
regds.