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+extended-join client capability specification
+---------------------------------------------
+
+Copyright (c) 2011 Kiyoshi Aman <kiyoshi.aman@gmail.com>
+
+Unlimited redistribution and modification of this document is allowed
+provided that the above copyright notice and this permission notice
+remains intact.
+
+The extended-join capability extends the JOIN message to include the
+account name, or a placeholder if the user hasn't identified with
+services. This capability MUST be referred to as 'extended-join' at
+capability negotiation time.
+
+When enabled, the JOIN message will designate the account name of the
+user when he/she joins a channel.
+
+The JOIN message is one of the following:
+
+    :nick!user@host JOIN #channelname accountname :Real Name
+
+This message represents that the user identified by nick!user@host has
+logged in to an acount prior to channel ingress. The penultimate
+parameter is the display name of that account. The last parameter is
+the user's GECOS.
+
+    :nick!user@host JOIN #channelname * :Real Name
+
+This message represents that the user has not logged in to an account
+prior to channel ingress. As the penultimate parameter is an asterisk,
+this means that an asterisk is not a valid account name (which it is
+not in P10 or TS6 or ESVID).
+
+Please see the documentation in account-notify.txt for how to take
+advantage of this capability.
+