diff --git a/xsl/callout.xsl b/xsl/callout.xsl
new file mode 100644
index 0000000..4c1950e
--- /dev/null
+++ b/xsl/callout.xsl
@@ -0,0 +1,69 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+   Copyright (c) 2007 Joel de Guzman <djowel -at- gmail.com>
+
+   Distributed under the Boost Software License, Version 1.0.
+   (See accompanying file LICENSE_1_0.txt or copy at
+   http://www.boost.org/LICENSE_1_0.txt)
+  -->
+<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
+                version="1.0">
+
+<xsl:import href="http://docbook.sourceforge.net/release/xsl/current/html/callout.xsl"/>
+<xsl:import href="relative-href.xsl"/>
+
+<xsl:template name="callout-bug">
+  <xsl:param name="conum" select='1'/>
+
+  <xsl:choose>
+    <xsl:when test="$callout.graphics != 0
+                    and $conum &lt;= $callout.graphics.number.limit">
+
+      <xsl:variable name="relative_callout_graphics_path">
+        <xsl:call-template name="href.target.relative">
+          <xsl:with-param name="target" select="$callout.graphics.path"/>
+        </xsl:call-template>
+      </xsl:variable>
+
+      <img src="{$relative_callout_graphics_path}{$conum}{$callout.graphics.extension}"
+           alt="{$conum}" border="0"/>
+    </xsl:when>
+
+    <xsl:when test="$callout.unicode != 0
+                    and $conum &lt;= $callout.unicode.number.limit">
+      <xsl:choose>
+        <xsl:when test="$callout.unicode.start.character = 10102">
+          <xsl:choose>
+            <xsl:when test="$conum = 1">&#10102;</xsl:when>
+            <xsl:when test="$conum = 2">&#10103;</xsl:when>
+            <xsl:when test="$conum = 3">&#10104;</xsl:when>
+            <xsl:when test="$conum = 4">&#10105;</xsl:when>
+            <xsl:when test="$conum = 5">&#10106;</xsl:when>
+            <xsl:when test="$conum = 6">&#10107;</xsl:when>
+            <xsl:when test="$conum = 7">&#10108;</xsl:when>
+            <xsl:when test="$conum = 8">&#10109;</xsl:when>
+            <xsl:when test="$conum = 9">&#10110;</xsl:when>
+            <xsl:when test="$conum = 10">&#10111;</xsl:when>
+          </xsl:choose>
+        </xsl:when>
+        <xsl:otherwise>
+          <xsl:message>
+            <xsl:text>Don't know how to generate Unicode callouts </xsl:text>
+            <xsl:text>when $callout.unicode.start.character is </xsl:text>
+            <xsl:value-of select="$callout.unicode.start.character"/>
+          </xsl:message>
+          <xsl:text>(</xsl:text>
+          <xsl:value-of select="$conum"/>
+          <xsl:text>)</xsl:text>
+        </xsl:otherwise>
+      </xsl:choose>
+    </xsl:when>
+    <xsl:otherwise>
+      <xsl:text>(</xsl:text>
+      <xsl:value-of select="$conum"/>
+      <xsl:text>)</xsl:text>
+    </xsl:otherwise>
+  </xsl:choose>
+</xsl:template>
+
+</xsl:stylesheet>
diff --git a/xsl/html.xsl b/xsl/html.xsl
index 19e344a..6924bd9 100644
--- a/xsl/html.xsl
+++ b/xsl/html.xsl
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!--
    Copyright (c) 2002 Douglas Gregor <doug.gregor -at- gmail.com>
-  
+
    Distributed under the Boost Software License, Version 1.0.
    (See accompanying file LICENSE_1_0.txt or copy at
    http://www.boost.org/LICENSE_1_0.txt)
@@ -20,6 +20,7 @@
   <xsl:import href="admon.xsl"/>
   <xsl:import href="xref.xsl"/>
   <xsl:import href="relative-href.xsl"/>
+  <xsl:import href="callout.xsl"/>
 
   <xsl:param name="admon.style"/>
   <xsl:param name="admon.graphics">1</xsl:param>
@@ -36,7 +37,7 @@
   <xsl:param name="doc.standalone">false</xsl:param>
   <xsl:param name="chunker.output.indent">yes</xsl:param>
   <xsl:param name="toc.max.depth">2</xsl:param>
-  
+
 <xsl:param name="admon.style">
     <!-- Remove the style. Let the CSS do the styling -->
 </xsl:param>
@@ -69,22 +70,22 @@ set       toc,title
     <xsl:param name="text"/>
 
     <!-- Remove the "$Date: " -->
-    <xsl:variable name="text.noprefix" 
+    <xsl:variable name="text.noprefix"
       select="substring-after($text, '$Date: ')"/>
 
     <!-- Grab the year -->
     <xsl:variable name="year" select="substring-before($text.noprefix, '/')"/>
-    <xsl:variable name="text.noyear" 
+    <xsl:variable name="text.noyear"
       select="substring-after($text.noprefix, '/')"/>
 
     <!-- Grab the month -->
     <xsl:variable name="month" select="substring-before($text.noyear, '/')"/>
-    <xsl:variable name="text.nomonth" 
+    <xsl:variable name="text.nomonth"
       select="substring-after($text.noyear, '/')"/>
 
     <!-- Grab the year -->
     <xsl:variable name="day" select="substring-before($text.nomonth, ' ')"/>
-    <xsl:variable name="text.noday" 
+    <xsl:variable name="text.noday"
       select="substring-after($text.nomonth, ' ')"/>
 
     <!-- Get the time -->
@@ -116,27 +117,27 @@ set       toc,title
     <xsl:param name="text"/>
 
     <!-- Remove the "$Date: " -->
-    <xsl:variable name="text.noprefix" 
+    <xsl:variable name="text.noprefix"
       select="substring-after($text, '$Date: ')"/>
 
     <!-- Grab the year -->
     <xsl:variable name="year" select="substring-before($text.noprefix, '-')"/>
-    <xsl:variable name="text.noyear" 
+    <xsl:variable name="text.noyear"
       select="substring-after($text.noprefix, '-')"/>
 
     <!-- Grab the month -->
     <xsl:variable name="month" select="substring-before($text.noyear, '-')"/>
-    <xsl:variable name="text.nomonth" 
+    <xsl:variable name="text.nomonth"
       select="substring-after($text.noyear, '-')"/>
 
     <!-- Grab the year -->
     <xsl:variable name="day" select="substring-before($text.nomonth, ' ')"/>
-    <xsl:variable name="text.noday" 
+    <xsl:variable name="text.noday"
       select="substring-after($text.nomonth, ' ')"/>
 
     <!-- Get the time -->
     <xsl:variable name="time" select="substring-before($text.noday, ' ')"/>
-    <xsl:variable name="text.notime" 
+    <xsl:variable name="text.notime"
       select="substring-after($text.noday, ' ')"/>
 
     <!-- Get the timezone -->
@@ -190,14 +191,14 @@ set       toc,title
     <table width="100%">
       <tr>
         <td align="left">
-          <xsl:variable name="revision-nodes" 
+          <xsl:variable name="revision-nodes"
             select="ancestor-or-self::*
                     [not (attribute::rev:last-revision='')]"/>
           <xsl:if test="count($revision-nodes) &gt; 0">
             <xsl:variable name="revision-node"
               select="$revision-nodes[last()]"/>
             <xsl:variable name="revision-text">
-              <xsl:value-of 
+              <xsl:value-of
                 select="normalize-space($revision-node/attribute::rev:last-revision)"/>
             </xsl:variable>
             <xsl:if test="string-length($revision-text) &gt; 0">
@@ -223,7 +224,7 @@ set       toc,title
         </td>
         <td align="right">
           <small>
-            <xsl:apply-templates select="ancestor::*/*/copyright" 
+            <xsl:apply-templates select="ancestor::*/*/copyright"
               mode="boost.footer"/>
           </small>
         </td>