diff --git a/xep-0158.xml b/xep-0158.xml
index 203cc781..22e63e6b 100644
--- a/xep-0158.xml
+++ b/xep-0158.xml
@@ -25,6 +25,12 @@
   <shortname>NOT_YET_ASSIGNED</shortname>
   &ianpaterson;
   &stpeter;
+  <revision>
+    <version>0.10</version>
+    <date>2008-08-06</date>
+    <initials>psa</initials>
+    <remark><p>Modified examples to track changes to XEP-0231; to avoid confusion with cid URIs, changed name of challenge ID form field from cid to challenge.</p></remark>
+  </revision>
   <revision>
     <version>0.9</version>
     <date>2008-05-12</date>
@@ -154,7 +160,7 @@
         <value>urn:xmpp:tmp:challenge</value>
       </field>
       <field type='hidden' var='from'><value>innocent@victim.com</value></field>
-      <field type='hidden' var='cid'><value>F3A6292C</value></field>
+      <field type='hidden' var='challenge'><value>F3A6292C</value></field>
       <field type='hidden' var='sid'><value>spam1</value></field>
       <field var='ocr' label='Enter the text you see'>
         <media xmlns='urn:xmpp:tmp:media-element'
@@ -163,8 +169,9 @@
           <uri type='image/jpeg'>
             http://www.victim.com/challenges/ocr.jpeg?F3A6292C
           </uri>
-          <data xmlns='urn:xmpp:tmp:data-element'
-                type='image/jpeg'> ** Base64 encoded image ** </data>
+          <uri type='image/jpeg'>
+            cid:99f2fea6-63e0-11dd-88e6-001143d5d5db@victim.com
+          </uri>
         </media>
       </field>
       <field var='picture_recog' label='Identify the picture'>
@@ -174,8 +181,9 @@
           <uri type='image/jpeg'>
             http://www.victim.com/challenges/picture.jpeg?F3A6292C
           </uri>
-          <data xmlns='urn:xmpp:tmp:data-element'
-                type='image/jpeg'> ** Base64 encoded image ** </data>
+          <uri type='image/jpeg'>
+            cid:1f2dc6fe-63e2-11dd-9d43-001143d5d5db@victim.com
+          </uri>
         </media>
       </field>
       <field var='speech_recog' label='Enter the words you hear'>
@@ -201,8 +209,15 @@
       <field label='93C7A' type='text-single' var='SHA-256'/>
     </x>
   </challenge>
+  <data xmlns='urn:xmpp:tmp:data-element'
+        cid='99f2fea6-63e0-11dd-88e6-001143d5d5db@victim.com'
+        type='image/jpeg'/>
+  <data xmlns='urn:xmpp:tmp:data-element'
+        cid='1f2dc6fe-63e2-11dd-9d43-001143d5d5db@victim.com'
+        type='image/jpeg'/>
 </message>
-    ]]></example>
+      ]]></example>
+      <p>The sender then would retrieve the media data via HTTP or (for the cid: UROs) via XMPP as described in &xep0231;.</p>
     </section3>
 
     <section3 topic='Response Stanza' anchor='protocol-response'>
@@ -248,7 +263,7 @@
         <value>urn:xmpp:tmp:challenge</value>
       </field>
       <field var='from'><value>innocent@victim.com</value></field>
-      <field var='cid'><value>F3A6292C</value></field>
+      <field var='challenge'><value>F3A6292C</value></field>
       <field var='sid'><value>spam1</value></field>
       <field var='ocr'><value>7nHL3</value></field>
     </x>
@@ -310,7 +325,7 @@
         <value>urn:xmpp:tmp:challenge</value>
       </field>
       <field type='hidden' var='from'><value>innocent@victim.com</value></field>
-      <field type='hidden' var='cid'><value>73DE28A2</value></field>
+      <field type='hidden' var='challenge'><value>73DE28A2</value></field>
       <field type='hidden' var='sid'><value>spam2</value></field>
       <field type='hidden' var='answers'><value>2</value></field>
       <field var='ocr' label='Enter the text you see'>
@@ -320,6 +335,9 @@
           <uri type='image/jpeg'>
             http://www.victim.com/challenges/ocr.jpeg?F3A6292C
           </uri>
+          <uri type='image/jpeg'>
+            cid:99f2fea6-63e0-11dd-88e6-001143d5d5db@victim.com
+          </uri>
         </media>
       </field>
       <field var='audio_recog' label='Describe the sound you hear'>
@@ -351,7 +369,7 @@
         <value>urn:xmpp:tmp:challenge</value>
       </field>
       <field var='from'><value>innocent@victim.com</value></field>
-      <field var='cid'><value>73DE28A2</value></field>
+      <field var='challenge'><value>73DE28A2</value></field>
       <field var='sid'><value>spam2</value></field>
       <field var='answers'><value>2</value></field>
       <field var='qa'><value>red</value></field>
@@ -380,7 +398,7 @@
       <field type='hidden' var='FORM_TYPE'>
         <value>urn:xmpp:tmp:challenge</value>
       </field>
-      <field type='hidden' var='cid'><value>F3A6292C</value></field>
+      <field type='hidden' var='challenge'><value>F3A6292C</value></field>
       <field type='hidden' var='sid'><value>reg1</value></field>
       <field type='hidden' var='answers'><value>3</value></field>
       <field var='ocr' label='Enter the text you see'>
@@ -417,7 +435,7 @@
       <field var='FORM_TYPE'>
         <value>urn:xmpp:tmp:challenge</value>
       </field>
-      <field var='cid'><value>F3A6292C</value></field>
+      <field var='challenge'><value>F3A6292C</value></field>
       <field var='sid'><value>reg1</value></field>
       <field var='answers'><value>3</value></field>
       <field var='ocr'><value>7nHL3</value></field>
@@ -452,7 +470,7 @@
         <value>urn:xmpp:tmp:challenge</value>
       </field>
       <field type='hidden' var='from'><value>friendly-chat@muc.victim.com</value></field>
-      <field type='hidden' var='cid'><value>A4C7303D</value></field>
+      <field type='hidden' var='challenge'><value>A4C7303D</value></field>
       <field var='ocr' label='Enter the text you see'>
         <media xmlns='urn:xmpp:tmp:media-element'
                height='80'
@@ -471,8 +489,9 @@
           <uri type='image/jpeg'>
             http://www.victim.com/challenges/picture.jpeg?A4C7303D
           </uri>
-          <data xmlns='urn:xmpp:tmp:data-element'
-                type='image/jpeg'> ** Base64 encoded image ** </data>
+          <uri type='image/jpeg'>
+            cid:1f2dc6fe-63e2-11dd-9d43-001143d5d5db@victim.com
+          </uri>
         </media>
       </field>
       <field var='speech_recog' label='Enter the words you hear'>
@@ -498,6 +517,12 @@
       <field label='93C7A' type='text-single' var='SHA-256'/>
     </x>
   </challenge>
+  <data xmlns='urn:xmpp:tmp:data-element'
+        cid='99f2fea6-63e0-11dd-88e6-001143d5d5db@victim.com'
+        type='image/jpeg'/>
+  <data xmlns='urn:xmpp:tmp:data-element'
+        cid='1f2dc6fe-63e2-11dd-9d43-001143d5d5db@victim.com'
+        type='image/jpeg'/>
 </message>
   ]]></example>
 </section1>
@@ -616,7 +641,7 @@
         <value>urn:xmpp:tmp:challenge</value>
       </field>
       <field type='hidden' var='from'><value>innocent@victim.com</value></field>
-      <field type='hidden' var='cid'><value>F3A6292C</value></field>
+      <field type='hidden' var='challenge'><value>F3A6292C</value></field>
       <field type='hidden' var='sid'><value>spam1</value></field>
       <field label='Type the color of a stop light' type='text-single' var='qa'/>
       <field label='93C7A' type='text-single' var='SHA-256'/>
@@ -696,7 +721,7 @@
       type='text-single'
       label='text associated with a sound'/>
   <field
-      var='cid'
+      var='challenge'
       type='hidden'
       label='challenge ID'/>
   <field
@@ -761,7 +786,7 @@
       type='text-single'
       label='text associated with a sound'/>
   <field
-      var='cid'
+      var='challenge'
       type='hidden'
       label='challenge ID'/>
   <field