diff --git a/.hgtags b/.hgtags
index 8b14343c3c..175d913779 100644
--- a/.hgtags
+++ b/.hgtags
@@ -1,57 +1,59 @@
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+1f0a01c93d305f1ab636c68b67346659c5b957f7 weekly.2009-11-06
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+c5c62aeb6267e124cf05f9622e28dbd0dc6b971d release.r56
 c5c62aeb6267e124cf05f9622e28dbd0dc6b971d release
diff --git a/doc/devel/release.html b/doc/devel/release.html
index c7691c7668..993899522e 100644
--- a/doc/devel/release.html
+++ b/doc/devel/release.html
@@ -5,7 +5,7 @@
 <p>This page summarizes the changes between tagged releases of Go.
 For full details, see the <a href="http://code.google.com/p/go/source/list">Mercurial change log</a>.</p>
 
-<h3 id="2011-03-07">2011-03-07</h3>
+<h3 id="2011-03-07">2011-03-07 (r56)</h3>
 
 <pre>
 This release includes changes to the reflect and path packages.
diff --git a/src/version.bash b/src/version.bash
index 0e64831508..b3df0e91a8 100755
--- a/src/version.bash
+++ b/src/version.bash
@@ -17,7 +17,10 @@ if [ $? != 0 ]; then
 fi
 
 # Find most recent known release tag.
-TAG=$(hg tags | awk '$1~/^release\./ {print $1}' | sed -n 1p)
+TAG=$(hg tags |
+	sort -rn -k2 |
+	awk -vver=$VERSION '$2 <= ver && $1~/^(release|weekly)\./ {print $1}' |
+	sed -n 1p)
 
 if [ "$TAG" != "" ]; then
 	VERSION="$TAG $VERSION"