>> Was jPDL modelling language support droped? <<
Yes. In jBPM5 processes are represented via with BPMN2.0 standard. jPDL is/was a propriatary markup representation which did not follow any standards. You can however use the jBPM Designer to migrate your jPDL-based processes to BPMN2.0 ( see http://vimeo.com/30857949, http://www.schabell.org/2011/10/jbpm-migration-tooling-available-in.html ). This is currently consideted an experimental feature but should help you get started.
>> RedHat SOA <<
jBPM 3.x is still supported by Red Hat. Future versions of BRMS/SOA will include jBPM5 and thus also BPMN2.0.
>> BPMN2 designers <<
Currently you have the options of the Eclipre ruleflow editor ( http://www.jboss.org/jbpm/components/eclipse-plugin ) and the jBPM Designer ( http://www.jboss.org/jbpm/components/designer ). The Eclipse modeller is currnetly undergoing major work. We believe it will be ready for the community very soon.