BPEL Mapper and elements defined by reference in schema

Hello All, I define in a schema a complex type where one or more elements are defined by reference. In order to define the "in and out" of my WSDL Operations, I use this complex type (designed with some element defined by reference) With Open-ESB BPEL Mapper, I design an "Assign" activity with relationships coming from or arriving on these elements defined by reference. BPEL Mapper represents these relationships by a line. The relationship is correctly reported in the BPEL resource code with the tags as well. But when I leave the mapper and come back the line has been erased. This happened only for the element defined by reference in a schema document. Strictly speaking, it is not a big issue because BPEL document is correct. But when I introduce Open ESB to my customers, they want me to use theirs wsdl for a proof of concept and sometimes they use "ref" in theirs xml schema definitions. Event if open-esb works well, it does not look like very clean and professional when the relationship disappear in the BPEL Mapper I am using Netbeans 6.1 development version provide with the package open-ESB. Does someone found a bypass for getting around this bug. Thanks for your help Paul