At the moment, value converters (which is the base for the simplified dmr format) are supported only for command arguments but not operation requests.

example:
/subsystem=ee:write-attribute(name=global-modules, value=["org.apache.log4j"]) ==> failed with JBAS014798/JBAS014746

workaround:
/subsystem=ee:write-attribute(name=global-modules,value=[

])