Karl: Could you tell me the pointer to the standard spec. of the asynchronous operation binding you mentioned in the telecon? I've found that WS-Addressing has "message information headers", which can carry the information that is necessary to implement asynchronous operations, but what you mentioned seems to be more than that... -- Takuya Araki Grid System Technology Group Internet Systems Research Laboratories NEC Corporation <t-araki@dc.jp.nec.com>