diff --git a/sql/ha_innobase.cc b/sql/ha_innobase.cc
index 3a71da6ba84..836a1a4331e 100644
--- a/sql/ha_innobase.cc
+++ b/sql/ha_innobase.cc
@@ -2961,7 +2961,8 @@ ha_innobase::records_in_range(
 	KEY*		key;
 	dict_index_t*	index;
 	mysql_byte*	key_val_buff2 	= (mysql_byte*) my_malloc(
-							table->reclength,
+						  table->reclength
+      						+ table->max_key_length + 100,
 								MYF(MY_WME));
 	dtuple_t*	range_start;
 	dtuple_t*	range_end;
diff --git a/sql/ha_innobase.h b/sql/ha_innobase.h
index b6419a5e74e..b1613c2503c 100644
--- a/sql/ha_innobase.h
+++ b/sql/ha_innobase.h
@@ -96,10 +96,12 @@ class ha_innobase: public handler
   	uint max_record_length() const { return HA_MAX_REC_LENGTH; }
   	uint max_keys()          const { return MAX_KEY; }
   	uint max_key_parts()     const { return MAX_REF_PARTS; }
-				/* An InnoDB page must store >= 2 keys:
-				max key length is therefore set to 7000
-				bytes */
-  	uint max_key_length()    const { return 7000; }
+				/* An InnoDB page must store >= 2 keys;
+				a secondary key record must also contain the
+				primary key value:
+				max key length is therefore set to slightly
+				less than 1 / 4 of page size which is 16 kB */
+  	uint max_key_length()    const { return 3500; }
   	bool fast_key_read()	 { return 1;}
 	key_map keys_to_use_for_scanning() { return ~(key_map) 0; }
   	bool has_transactions()  { return 1;}