(last updated 2012年09月23日)
Resource Identifier (RI) Scheme name: message 
Status: provisional
Scheme syntax:
 message:<message-id> or message://<message-id>
Scheme semantics:
 Direct link to specific email message
Encoding considerations:
 Unknown, use with care.
Applications/protocols that use this scheme name:
 Supported by Mail since OS X 10.5
Interoperability considerations:
 Unknown, use with care.
 May be unsuitable for open use on the public internet.
Security considerations:
 Unknown, use with care.
Contact:
 Registering party: Dave Thaler <dthaler&microsoft.com>
 Scheme creator: Apple
Author/Change controller:
 Either the registering party or someone who is verified to represent
 the scheme creator. See previous answer.
References:
 http://daringfireball.net/2007/12/message_urls_leopard_mail
(file created 2012年09月23日)</div><div class="naked_ctrl">
<form action="/index.cgi/contrast" method="get" name="gate">
<p><a href="http://altstyle.alfasado.net">AltStyle</a> によって変換されたページ <a href="http://www.iana.org/assignments/uri-schemes/prov/message">(-&gt;オリジナル)</a>
/ <label>アドレス: <input type="text" name="naked_post_url" value="http://www.iana.org/assignments/uri-schemes/prov/message" size="22" /></label> <label>モード: <select name="naked_post_mode">
<option value="default">デフォルト</option>
<option value="speech">音声ブラウザ</option>
<option value="ruby">ルビ付き</option>
<option value="contrast" selected="selected">配色反転</option>
<option value="larger-text">文字拡大</option>
<option value="mobile">モバイル</option>
</select>
<input type="submit" value="表示" />
</p>
</form>
</div>