corrected rndc sign syntax

doc/arm/Bv9ARM-book.xml

@@ -18,7 +18,7 @@
  - PERFORMANCE OF THIS SOFTWARE.
 -->
 
-<!-- File: $Id: Bv9ARM-book.xml,v 1.445 2009/11/10 19:49:32 each Exp $ -->
+<!-- File: $Id: Bv9ARM-book.xml,v 1.446 2009/11/26 00:20:28 each Exp $ -->
 <book xmlns:xi="http://www.w3.org/2001/XInclude">
   <title>BIND 9 Administrator Reference Manual</title>
 
@@ -10431,7 +10431,8 @@ zone <replaceable>zone_name</replaceable> <optional><replaceable>class</replacea
                   <para>
                     <command>auto-dnssec allow;</command> permits
                     keys to be updated and the zone re-signed whenever the
-                    user issues the command <command>rndc sign</command>.
+                    user issues the command <command>rndc sign
+                    <replaceable>zonename</replaceable></command>.
                   </para>
                   <para>
                     <command>auto-dnssec maintain;</command> includes the