diff -Nur -x bdb mysql-5.0.26/client/mysql_priv.h mysql-5.0.26.kill_query/client/mysql_priv.h
--- mysql-5.0.26/client/mysql_priv.h	2006-10-04 04:24:43.000000000 -0700
+++ mysql-5.0.26.kill_query/client/mysql_priv.h	2006-10-23 18:38:33.000000000 -0700
@@ -83,7 +83,7 @@
 			       CHARSET_INFO *from_cs,
 			       uint32 max_res_length,
 			       CHARSET_INFO *to_cs, uint32 *result_length);
-void kill_one_thread(THD *thd, ulong id, bool only_kill_query);
+void kill_one_thread(THD *thd, ulong id, query_id_t query_id, bool only_kill_query);
 bool net_request_file(NET* net, const char* fname);
 char* query_table_status(THD *thd,const char *db,const char *table_name);
 
diff -Nur -x bdb mysql-5.0.26/sql/mysql_priv.h mysql-5.0.26.kill_query/sql/mysql_priv.h
--- mysql-5.0.26/sql/mysql_priv.h	2006-10-04 04:24:43.000000000 -0700
+++ mysql-5.0.26.kill_query/sql/mysql_priv.h	2006-10-23 18:38:33.000000000 -0700
@@ -83,7 +83,7 @@
 			       CHARSET_INFO *from_cs,
 			       uint32 max_res_length,
 			       CHARSET_INFO *to_cs, uint32 *result_length);
-void kill_one_thread(THD *thd, ulong id, bool only_kill_query);
+void kill_one_thread(THD *thd, ulong id, query_id_t query_id, bool only_kill_query);
 bool net_request_file(NET* net, const char* fname);
 char* query_table_status(THD *thd,const char *db,const char *table_name);
 
diff -Nur -x bdb mysql-5.0.26/sql/share/errmsg.txt mysql-5.0.26.kill_query/sql/share/errmsg.txt
--- mysql-5.0.26/sql/share/errmsg.txt	2006-10-04 04:24:10.000000000 -0700
+++ mysql-5.0.26.kill_query/sql/share/errmsg.txt	2006-10-24 15:53:26.000000000 -0700
@@ -5633,4 +5633,6 @@
 	eng "String '%-.70s' is too long for %s (should be no longer than %d)"
 ER_NON_INSERTABLE_TABLE  
 	eng "The target table %-.100s of the %s is not insertable-into"
+ER_KILL_QUERY_ID_MISMATCH
+        eng "Cannot kill thread %lu, Query ID mismatch"
 
diff -Nur -x bdb mysql-5.0.26/sql/sql_parse.cc mysql-5.0.26.kill_query/sql/sql_parse.cc
--- mysql-5.0.26/sql/sql_parse.cc	2006-10-04 04:24:42.000000000 -0700
+++ mysql-5.0.26.kill_query/sql/sql_parse.cc	2006-10-24 16:02:43.000000000 -0700
@@ -2054,7 +2054,7 @@
   {
     statistic_increment(thd->status_var.com_stat[SQLCOM_KILL], &LOCK_status);
     ulong id=(ulong) uint4korr(packet);
-    kill_one_thread(thd,id,false);
+    kill_one_thread(thd,id,0,false);
     break;
   }
   case COM_SET_OPTION:
@@ -4054,7 +4054,18 @@
   }
   case SQLCOM_KILL:
   {
-    Item *it= (Item *)lex->value_list.head();
+    query_id_t query_id= 0;
+    Item *q_item, *it= (Item *)lex->value_list.pop();
+    if(!lex->value_list.is_empty())
+    {
+      q_item= lex->value_list.pop();
+      if((!q_item->fixed && q_item->fix_fields(lex->thd, &q_item)) || q_item->check_cols(1))
+      {
+        my_message(ER_SET_CONSTANTS_ONLY, ER(ER_SET_CONSTANTS_ONLY), MYF(0));
+	goto error;
+      }
+      query_id= (ulong)q_item->val_int();
+    }
 
     if ((!it->fixed && it->fix_fields(lex->thd, &it)) || it->check_cols(1))
     {
@@ -4062,7 +4073,7 @@
 		 MYF(0));
       goto error;
     }
-    kill_one_thread(thd, (ulong)it->val_int(), lex->type & ONLY_KILL_QUERY);
+    kill_one_thread(thd, (ulong)it->val_int(), query_id, lex->type & ONLY_KILL_QUERY);
     break;
   }
 #ifndef NO_EMBEDDED_ACCESS_CHECKS
@@ -6883,15 +6894,23 @@
     kill_one_thread()
     thd			Thread class
     id			Thread id
+    query_id_arg	Query id to match against
+    only_kill_query	Kill only query or thread and query
 
   NOTES
     This is written such that we have a short lock on LOCK_thread_count
+    
+    If query_id_arg != 0, the thread will only be killed if the thread's
+       current query matches.
+
+    If only_kill_query == true, then only the current query will be killed,
+       and not the entire thread
 */
 
-void kill_one_thread(THD *thd, ulong id, bool only_kill_query)
+void kill_one_thread(THD *thd, ulong id, query_id_t query_id_arg, bool only_kill_query)
 {
   THD *tmp;
-  uint error=ER_NO_SUCH_THREAD;
+  uint error= ER_NO_SUCH_THREAD;
   VOID(pthread_mutex_lock(&LOCK_thread_count)); // For unlink from list
   I_List_iterator<THD> it(threads);
   while ((tmp=it++))
@@ -6902,24 +6921,40 @@
       break;
     }
   }
-  VOID(pthread_mutex_unlock(&LOCK_thread_count));
+  /* Need to hold the lock through THD::awake to be sure another query 
+     (with a different query_id_arg) is not started. */
+  if (!query_id_arg)
+    VOID(pthread_mutex_unlock(&LOCK_thread_count));
   if (tmp)
   {
     if ((thd->security_ctx->master_access & SUPER_ACL) ||
 	!strcmp(thd->security_ctx->user, tmp->security_ctx->user))
     {
-      tmp->awake(only_kill_query ? THD::KILL_QUERY : THD::KILL_CONNECTION);
-      error=0;
+      if (query_id_arg != 0 && query_id_arg != tmp->query_id)
+      {
+        error= ER_KILL_QUERY_ID_MISMATCH;
+        my_error(error, MYF(0), id);
+      }
+      else
+      {
+        tmp->awake(only_kill_query ? THD::KILL_QUERY : THD::KILL_CONNECTION);
+        error= 0;
+      }
     }
     else
-      error=ER_KILL_DENIED_ERROR;
+    {
+      error= ER_KILL_DENIED_ERROR;
+      my_error(error, MYF(0), id);
+    }
+    
     pthread_mutex_unlock(&tmp->LOCK_delete);
+    /* release the lock now only if we were checking for specific query */
+    if (query_id_arg)
+      VOID(pthread_mutex_unlock(&LOCK_thread_count));
   }
 
   if (!error)
     send_ok(thd);
-  else
-    my_error(error, MYF(0), id);
 }
 
 
diff -Nur -x bdb mysql-5.0.26/sql/sql_show.cc mysql-5.0.26.kill_query/sql/sql_show.cc
--- mysql-5.0.26/sql/sql_show.cc	2006-10-04 04:24:21.000000000 -0700
+++ mysql-5.0.26.kill_query/sql/sql_show.cc	2006-10-24 16:41:22.000000000 -0700
@@ -1266,6 +1266,7 @@
   uint   command;
   const char *user,*host,*db,*proc_info,*state_info;
   char *query;
+  query_id_t query_id;
 };
 
 #ifdef HAVE_EXPLICIT_TEMPLATE_INSTANTIATION
@@ -1293,6 +1294,11 @@
   field->maybe_null=1;
   field_list.push_back(field=new Item_empty_string("Info",max_query_length));
   field->maybe_null=1;
+  if (verbose)
+  {
+    field_list.push_back(field=new Item_int("Query_Id",FIELD_TYPE_LONGLONG));
+    field->maybe_null= 1;
+  }
   if (protocol->send_fields(&field_list,
                             Protocol::SEND_NUM_ROWS | Protocol::SEND_EOF))
     DBUG_VOID_RETURN;
@@ -1366,7 +1372,8 @@
           */
           uint length= min(max_query_length, tmp->query_length);
           thd_info->query=(char*) thd->strmake(tmp->query,length);
-        }
+	}
+	thd_info->query_id= tmp->query_id;
         thread_infos.append(thd_info);
       }
     }
@@ -1392,6 +1399,13 @@
       protocol->store_null();
     protocol->store(thd_info->state_info, system_charset_info);
     protocol->store(thd_info->query, system_charset_info);
+    if (verbose)
+    {
+      if (thd_info->query)
+        protocol->store(thd_info->query_id);
+      else
+        protocol->store_null();
+    }
     if (protocol->write())
       break; /* purecov: inspected */
   }
diff -Nur -x bdb mysql-5.0.26/sql/sql_yacc.yy mysql-5.0.26.kill_query/sql/sql_yacc.yy
--- mysql-5.0.26/sql/sql_yacc.yy	2006-10-04 04:24:23.000000000 -0700
+++ mysql-5.0.26.kill_query/sql/sql_yacc.yy	2006-10-23 18:38:14.000000000 -0700
@@ -6883,19 +6883,31 @@
 /* kill threads */
 
 kill:
-	KILL_SYM { Lex->sql_command= SQLCOM_KILL; } kill_option expr
+	KILL_SYM
 	{
-	  LEX *lex=Lex;
+	  LEX *lex= Lex;
+  	  lex->sql_command= SQLCOM_KILL;
 	  lex->value_list.empty();
-	  lex->value_list.push_front($4);
+	} 
+	kill_option expr kill_with_query_option
+	{
+	  Lex->value_list.push_front($4);
 	};
 
+
+
 kill_option:
 	/* empty */	 { Lex->type= 0; }
 	| CONNECTION_SYM { Lex->type= 0; }
 	| QUERY_SYM      { Lex->type= ONLY_KILL_QUERY; }
         ;
 
+kill_with_query_option:
+	/* empty */
+	| WITH QUERY_SYM expr { Lex->value_list.push_front($3); }
+	;
+
+
 /* change database */
 
 use:	USE_SYM ident