[ebxml-dev] Query on usage of Acknowledgement element

Hi! ebXML folks!!!!!!!!!
welcome to ebXML discussion after a long break

specification says
The Acknowledgment element is an optional element that is used by one
Message Service Handler to indicate that another Message Service Handler
has received a message.  The RefToMessageId in a message containing an
Acknowledgement element is used to identify the message being
acknowledged by its MessageId.
The Acknowledgment element consists of the following elements and
attributes:
*	a Timestamp element
*	a From element
*	zero or more ds:Reference element(s)
*	a REQUIRED SOAP mustUnderstand attribute (See section 8.4.11 for
details)
*	a REQUIRED SOAP actor attribute
*	a REQUIRED version attribute (See section 8.4.10 for details)
*	an id attribute (See section 8.2.5 for details)

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Now the Question is wether the Acknowledgement element comes to picture
only in MultiHop or is there any scope to appear in Single Hop. If it
appears in Single Hop,When will it become essential to use
Acknowledgement element in Single Hop.

Regards
kumar

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