diff --git a/BitKeeper/triggers/post-commit b/BitKeeper/triggers/post-commit
index 1c4608835d6..a38b1f5a068 100755
--- a/BitKeeper/triggers/post-commit
+++ b/BitKeeper/triggers/post-commit
@@ -20,13 +20,19 @@ if [ "$BK_STATUS" = OK ]
 then 
 
 CHANGESET=`bk -R prs -r+ -h -d':P:::I:' ChangeSet`
-BUG=`bk -R prs -r+ -h -d':C:' ChangeSet | sed -ne 's/^.*[Bb][Uu][Gg] *# *\([0-9][0-9]*\).*$/ BUG#\1/p'`
+BUG=`bk -R prs -r+ -h -d':C:' ChangeSet | sed -ne 's/^.*[Bb][Uu][Gg] *# *\([0-9][0-9]*\).*$/\1/p'`
 
 if [ "$BUG" = "" ]
 then
   TO=dev-public@mysql.com
+  BS=""
+  BH=""
 else
   TO=dev-bugs@mysql.com
+  BS=" BUG#$BUG"
+# need newline here
+  BH="X-Bug: $BUG
+"
 fi
 #++
 # dev-public@ / dev-bugs@
@@ -37,8 +43,8 @@ fi
 List-ID: <bk.mysql-$VERSION>
 From: $FROM
 To: $TO
-Subject: bk commit - $VERSION tree ($CHANGESET)$BUG
-
+Subject: bk commit - $VERSION tree ($CHANGESET)$BS
+$BH
 EOF
   bk changes -v -r+
   bk cset -r+ -d
@@ -53,14 +59,14 @@ EOF
 List-ID: <bk.mysql-$VERSION>
 From: $FROM
 To: $INTERNALS
-Subject: bk commit into $VERSION tree ($CHANGESET)
-
+Subject: bk commit into $VERSION tree ($CHANGESET)$BS
+$BH
 Below is the list of changes that have just been committed into a local
 $VERSION repository of $USER. When $USER does a push these changes will
 be propagated to the main repository and, within 24 hours after the
 push, to the public repository.
 For information on how to access the public repository
-see http://www.mysql.com/doc/I/n/Installing_source_tree.html
+see http://dev.mysql.com/doc/mysql/en/installing-source-tree.html
 
 EOF
   bk changes -v -r+
@@ -80,7 +86,7 @@ EOF
 List-ID: <bk.mysql-$VERSION>
 From: $FROM
 To: $DOCS
-Subject: bk commit - $VERSION tree (Manual) ($CHANGESET)
+Subject: bk commit - $VERSION tree (Manual) ($CHANGESET)$BS
 
 EOF
   bk changes -v -r+
diff --git a/mysql-test/r/select.result b/mysql-test/r/select.result
index cc90547722f..4c6ad1c34f0 100644
--- a/mysql-test/r/select.result
+++ b/mysql-test/r/select.result
@@ -2364,3 +2364,16 @@ EXPLAIN SELECT i FROM t1 WHERE i=1;
 table	type	possible_keys	key	key_len	ref	rows	Extra
 t1	const	PRIMARY	PRIMARY	4	const	1	Using index
 DROP TABLE t1;
+CREATE TABLE t1 ( a BLOB, INDEX (a(20)) );
+CREATE TABLE t2 ( a BLOB, INDEX (a(20)) );
+INSERT INTO t1 VALUES ('one'),('two'),('three'),('four'),('five');
+INSERT INTO t2 VALUES ('one'),('two'),('three'),('four'),('five');
+EXPLAIN SELECT * FROM t1 LEFT JOIN t2 USE INDEX (a) ON t1.a=t2.a;
+table	type	possible_keys	key	key_len	ref	rows	Extra
+t1	ALL	NULL	NULL	NULL	NULL	5	
+t2	ref	a	a	23	t1.a	5	
+EXPLAIN SELECT * FROM t1 LEFT JOIN t2 FORCE INDEX (a) ON t1.a=t2.a;
+table	type	possible_keys	key	key_len	ref	rows	Extra
+t1	ALL	NULL	NULL	NULL	NULL	5	
+t2	ref	a	a	23	t1.a	5	
+DROP TABLE t1, t2;
diff --git a/mysql-test/t/select.test b/mysql-test/t/select.test
index e6b1ffbe8d7..9be08b8390b 100644
--- a/mysql-test/t/select.test
+++ b/mysql-test/t/select.test
@@ -1909,3 +1909,18 @@ EXPLAIN SELECT i FROM t1 WHERE i=1;
 EXPLAIN SELECT i FROM t1 WHERE i=1;
 
 DROP TABLE t1;
+
+#
+# Test case for bug 7520: a wrong cost of the index for a BLOB field
+#
+
+CREATE TABLE t1 ( a BLOB, INDEX (a(20)) );
+CREATE TABLE t2 ( a BLOB, INDEX (a(20)) );
+
+INSERT INTO t1 VALUES ('one'),('two'),('three'),('four'),('five');
+INSERT INTO t2 VALUES ('one'),('two'),('three'),('four'),('five');
+
+EXPLAIN SELECT * FROM t1 LEFT JOIN t2 USE INDEX (a) ON t1.a=t2.a;
+EXPLAIN SELECT * FROM t1 LEFT JOIN t2 FORCE INDEX (a) ON t1.a=t2.a;
+
+DROP TABLE t1, t2;
diff --git a/sql/table.cc b/sql/table.cc
index 573fa11a4c4..244c7fa94f3 100644
--- a/sql/table.cc
+++ b/sql/table.cc
@@ -486,6 +486,7 @@ int openfrm(const char *name, const char *alias, uint db_stat, uint prgflag,
 	    if (!(field->flags & BINARY_FLAG))
 	      keyinfo->flags|= HA_END_SPACE_KEY;
 	  }
+          set_if_bigger(outparam->max_key_length, keyinfo->key_length);
 	  if (i == 0 && key != primary_key)
 	    field->flags |=
 	      ((keyinfo->flags & HA_NOSAME) &&