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review all IETF documents being processed by the IESG.  These comments were written with 
the intent of improving the operational aspects of the IETF drafts. Comments that are not 
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editors and WG chairs should treat these comments just like any other last call comments.

This document defines Extensible Provison Protocol (EPP) extension for unhandled namespace information
conveyed to the client. It allow the server return unhandled namespace information that the client can 
process later.
I think this document is well documented, however I do have a few questions for clarification.
Major issue:
Not found
Minor issues:
1.Section 1:
I am not sure how unhandled namespace information exchanging between the client and the service
is compliant with the negotiated services defined in [RFC5730]. Why error response is not best choice 
to return this unhandled namespace information for later handling.

2. Section 3.1/Section 3.2
For Unhandled Object-Level Extension in section 3.1 and Unhandled Command-Response Extension in section 3.2,
I see Template unhandled namespace response example for an unsupported command-response extension
is same as Template unhandled namespace response example for an unsupported object-level extension, which make me confused,
I am wondering how do we distinguish Unhandled Object-Level Extension from Unhandled Command-Response Extension in the XML snippet example.
Can you clarify this?

3. When we say converting from an object response to a general EPP response by the server, does it mean the [NAMESPACE-XML] variable
should be replaced by the object-level extension XML. Where these [NAMESPACE-XML] variable are stored in the server? Do we need to maintain the mapping
between [NAMESPACE-XML] variable and object-level extension XML? Can you clarify this?