diff --git a/webapps/docs/cluster-howto.xml b/webapps/docs/cluster-howto.xml
index cc753422e19f..cbab6fddc798 100644
--- a/webapps/docs/cluster-howto.xml
+++ b/webapps/docs/cluster-howto.xml
@@ -238,6 +238,18 @@ should be completed:</p>
   replication yields shorter request times, and synchronous replication guarantees the session
   to be replicated before the request returns.
 </p>
+<p>
+    In addition to <code>channelSendOptions</code>, the backup manager's
+    <code>mapSendOptions</code> attribute uses the same send-option flag
+    mechanism. This attribute controls how the replicated map within the
+    <code>BackupManager</code> sends its messages during session backup
+    operations.
+    Just like <code>channelSendOptions</code>, the value may be specified
+    either as an integer bitmask (e.g. <code>6</code>) or using the
+    human-readable option names (e.g. <code>"sync,use_ack"</code>), with
+    multiple names separated by commas. The same option names and flag
+    combinations apply to both attributes.
+</p>
 </section>
 
 <section name="Bind session after crash to failover node">
diff --git a/webapps/docs/config/cluster-manager.xml b/webapps/docs/config/cluster-manager.xml
index 6197baa47a9f..dc9279363295 100644
--- a/webapps/docs/config/cluster-manager.xml
+++ b/webapps/docs/config/cluster-manager.xml
@@ -227,12 +227,44 @@
   <subsection name="org.apache.catalina.ha.session.BackupManager Attributes">
     <attributes>
       <attribute name="mapSendOptions" required="false">
-        The backup manager uses a replicated map, this map is sending and
-        receiving messages. You can setup the flag for how this map is sending
-        messages, the default value is <code>6</code>(synchronous).<br/>
-        Note that if you use asynchronous messaging it is possible for update
-        messages for a session to be processed by the receiving node in a
-        different order to the order in which they were sent.
+        <p>
+          The backup manager uses a replicated map. This map sends and receives
+          messages internally. You can configure the flag that controls how this
+          map sends messages. The default value is <code>6</code> (synchronous).<br/>
+          Note that if you use asynchronous messaging it is possible for update
+          messages for a session to be processed by the receiving node in a
+          different order to the order in which they were sent.
+        </p>
+
+        <p>
+          The value may be specified either as an integer flag or using the
+          human-readable option names. These names are translated to their integer
+          values on startup.
+        </p>
+
+        <p>Some of the values are:<br/>
+          <code>Channel.SEND_OPTIONS_SYNCHRONIZED_ACK = 0x0004</code><br/>
+          <code>Channel.SEND_OPTIONS_ASYNCHRONOUS     = 0x0008</code><br/>
+          <code>Channel.SEND_OPTIONS_USE_ACK          = 0x0002</code><br/>
+          Therefore, the default <code>6</code> corresponds to
+          <code>sync,use_ack</code> (4 + 2).
+        </p>
+
+        <p>
+          Examples:<br/>
+          <code>mapSendOptions="6"</code> /
+          <code>mapSendOptions="sync,use_ack"</code><br/>
+          <code>mapSendOptions="8"</code> / <code>mapSendOptions="async"</code><br/>
+          <code>mapSendOptions="2"</code> / <code>mapSendOptions="use_ack"</code>
+        </p>
+
+        <p>
+          The valid option names are the same as for <code>channelSendOptions</code>:
+          "asynchronous" (alias "async"), "byte_message" (alias "byte"),
+          "multicast", "secure", "synchronized_ack" (alias "sync"), "udp",
+          "use_ack". Multiple names may be comma-separated, e.g.
+          <code>"async,multicast"</code>.
+        </p>
       </attribute>
       <attribute name="maxActiveSessions" required="false">
         The maximum number of active sessions that will be created by this
diff --git a/webapps/docs/config/cluster-valve.xml b/webapps/docs/config/cluster-valve.xml
index c353053afb6f..2cdf68d40ae7 100644
--- a/webapps/docs/config/cluster-valve.xml
+++ b/webapps/docs/config/cluster-valve.xml
@@ -131,7 +131,40 @@
         map sends messages. The default value is <code>6</code> (synchronous).
         Note that if you use asynchronous messaging it is possible for update
         messages to be processed by the receiving node in a different order to
-        the order in which they were sent.</p>
+        the order in which they were sent.
+        </p>
+
+        <p>
+          The value may be specified either as an integer flag or using the
+          human-readable option names. These names are translated to their
+          integer values on startup.
+        </p>
+
+        <p>Some of the values are:<br/>
+          <code>Channel.SEND_OPTIONS_SYNCHRONIZED_ACK = 0x0004</code><br/>
+          <code>Channel.SEND_OPTIONS_ASYNCHRONOUS     = 0x0008</code><br/>
+          <code>Channel.SEND_OPTIONS_USE_ACK          = 0x0002</code><br/>
+          Therefore, the default <code>6</code> corresponds to
+          <code>sync,use_ack</code> (4 + 2).
+        </p>
+
+        <p>
+          Examples:<br/>
+          <code>mapSendOptions="6"</code> /
+          <code>mapSendOptions="sync,use_ack"</code><br/>
+          <code>mapSendOptions="8"</code> /
+          <code>mapSendOptions="async"</code><br/>
+          <code>mapSendOptions="2"</code> /
+          <code>mapSendOptions="use_ack"</code>
+        </p>
+
+        <p>
+          The valid option names are the same as for
+          <code>channelSendOptions</code>: "asynchronous" (alias "async"),
+          "byte_message" (alias "byte"), "multicast", "secure",
+          "synchronized_ack" (alias "sync"), "udp", "use_ack". Multiple names
+          may be comma-separated, e.g. <code>"async,multicast"</code>.
+        </p>
       </attribute>
       <attribute name="requireReauthentication" required="false">
         <p>Default false. Flag to determine whether each request needs to be