diff --git a/doc/spec/control-spec.txt b/doc/spec/control-spec.txt
index 82ca09f768..1c0f85b6c2 100644
--- a/doc/spec/control-spec.txt
+++ b/doc/spec/control-spec.txt
@@ -431,15 +431,25 @@ $Id$
     "entry-guards"
       A series of lines listing the currently chosen entry guards, if any.
       Each is of the form:
-         ServerID  SP (Status-with-time / Status) CRLF
+         ServerID2 SP Status [SP ISOTime] CRLF
 
-         Status-with-time = ("down" / "unlisted") SP ISOTime
-         Status = ("up" / "never-connected")
+         Status-with-time = ("unlisted") SP ISOTime
+         Status = ("up" / "never-connected" / "down" /
+                      "unusable" / "unlisted" )
+
+         ServerID2 = Nickname / 40*HEXDIG
 
       [From 0.1.1.4-alpha to 0.1.1.10-alpha, this was called "helper-nodes".
        Tor still supports calling it that for now, but support will be
        removed in 0.1.3.x.]
 
+      [Older versions of Tor (before 0.1.2.x-final) generated 'down' instead
+       of unlisted/unusable.  Current Tors never generate 'down'.]
+
+      [XXXX ServerID2 differs from ServerID in not prefixing fingerprints
+       with a $.  This is an implementation error.  It would be nice to add
+       the $ back in if we can do so without breaking compatibility.]
+
     "accounting/enabled"
     "accounting/hibernating"
     "accounting/bytes"