diff --git a/share/cpim_grammar b/share/cpim_grammar
index 6f8b36d95..7ea914ca5 100644
Binary files a/share/cpim_grammar and b/share/cpim_grammar differ
diff --git a/src/chat/cpim/header/cpim-core-headers.cpp b/src/chat/cpim/header/cpim-core-headers.cpp
index 6d88fccca..1a85d7e81 100644
--- a/src/chat/cpim/header/cpim-core-headers.cpp
+++ b/src/chat/cpim/header/cpim-core-headers.cpp
@@ -49,7 +49,6 @@ MAKE_CORE_HEADER_IMPL(From);
 MAKE_CORE_HEADER_IMPL(To);
 MAKE_CORE_HEADER_IMPL(Cc);
 MAKE_CORE_HEADER_IMPL(DateTime);
-MAKE_CORE_HEADER_IMPL(MessageId);
 
 MAKE_CORE_HEADER_IMPL(Ns);
 MAKE_CORE_HEADER_IMPL(Require);
diff --git a/src/chat/cpim/header/cpim-core-headers.h b/src/chat/cpim/header/cpim-core-headers.h
index 0fa205011..1c7321ce4 100644
--- a/src/chat/cpim/header/cpim-core-headers.h
+++ b/src/chat/cpim/header/cpim-core-headers.h
@@ -72,7 +72,6 @@ namespace Cpim {
 	MAKE_CORE_HEADER(To, "To");
 	MAKE_CORE_HEADER(Cc, "cc");
 	MAKE_CORE_HEADER(DateTime, "DateTime");
-	MAKE_CORE_HEADER(MessageId, "Message-ID");
 	MAKE_CORE_HEADER(Ns, "NS");
 	MAKE_CORE_HEADER(Require, "Require");
 
diff --git a/src/chat/cpim/parser/cpim-parser.cpp b/src/chat/cpim/parser/cpim-parser.cpp
index ce8e3d5a4..3d34fcd71 100644
--- a/src/chat/cpim/parser/cpim-parser.cpp
+++ b/src/chat/cpim/parser/cpim-parser.cpp
@@ -137,7 +137,6 @@ namespace Cpim {
 			{ "To", &HeaderNode::createCoreHeader<ToHeader> },
 			{ "cc", &HeaderNode::createCoreHeader<CcHeader> },
 			{ "DateTime", &HeaderNode::createCoreHeader<DateTimeHeader> },
-			{ "Message-ID", &HeaderNode::createCoreHeader<MessageIdHeader> },
 			{ "Subject", &HeaderNode::createCoreHeader<SubjectHeader> },
 			{ "NS", &HeaderNode::createCoreHeader<NsHeader> },
 			{ "Require", &HeaderNode::createCoreHeader<RequireHeader> }
@@ -420,12 +419,6 @@ bool Cpim::Parser::coreHeaderIsValid<Cpim::DateTimeHeader> (const string &header
 	return true;
 }
 
-template<>
-bool Cpim::Parser::coreHeaderIsValid<Cpim::MessageIdHeader> (const string &headerValue) const {
-	L_D();
-	return LinphonePrivate::coreHeaderIsValid(d->grammar, "Message-ID", headerValue);
-}
-
 template<>
 bool Cpim::Parser::coreHeaderIsValid<Cpim::SubjectHeader> (const string &headerValue) const {
 	L_D();
diff --git a/src/chat/cpim/parser/cpim-parser.h b/src/chat/cpim/parser/cpim-parser.h
index 46864274a..bdb32f7e4 100644
--- a/src/chat/cpim/parser/cpim-parser.h
+++ b/src/chat/cpim/parser/cpim-parser.h
@@ -70,9 +70,6 @@ namespace Cpim {
 	template<>
 	bool Parser::coreHeaderIsValid<DateTimeHeader>(const std::string &headerValue) const;
 
-	template<>
-	bool Parser::coreHeaderIsValid<MessageIdHeader>(const std::string &headerValue) const;
-
 	template<>
 	bool Parser::coreHeaderIsValid<SubjectHeader>(const std::string &headerValue) const;
 
diff --git a/src/chat/cpim/parser/cpim-rules b/src/chat/cpim/parser/cpim-rules
index a0b866fee..bba8e019c 100644
--- a/src/chat/cpim/parser/cpim-rules
+++ b/src/chat/cpim/parser/cpim-rules
@@ -25,8 +25,6 @@ To-header-value = [ Formal-name ] "<" URI ">"
 DateTime-header = %d68.97.116.101.84.105.109.101 ": " DateTime-header-value
 DateTime-header-value = date-time
 
-Message-ID-header = %d77.101.115.115.97.103.101.45.73.68 ": " Token
-
 cc-header = %d99.99 ": " cc-header-value
 cc-header-value = [ Formal-name ] "<" URI ">"