diff -ur drupal-4.7.4/includes/bootstrap.inc drupal-4.7.4-patched/includes/bootstrap.inc
--- drupal-4.7.4/includes/bootstrap.inc	2006-08-03 14:53:15.000000000 +0100
+++ drupal-4.7.4-patched/includes/bootstrap.inc	2006-12-19 00:08:32.000000000 +0000
@@ -281,10 +281,11 @@
 function variable_set($name, $value) {
   global $conf;
 
-  db_lock_table('variable');
-  db_query("DELETE FROM {variable} WHERE name = '%s'", $name);
-  db_query("INSERT INTO {variable} (name, value) VALUES ('%s', '%s')", $name, serialize($value));
-  db_unlock_tables();
+// From chx's patch http://drupal.org/node/55516 http://drupal.org/files/issues/no_block.patch.txt
+  db_query_replace(
+    array("DELETE FROM {variable} WHERE name = '%s'", $name),
+    array("INSERT INTO {variable} (name, value) VALUES ('%s', '%s')", $name, serialize($value))
+  );
 
   cache_clear_all('variables');
 
@@ -368,12 +369,11 @@
  *   A string containing HTTP header information for cached pages.
  */
 function cache_set($cid, $data, $expire = CACHE_PERMANENT, $headers = NULL) {
-  db_lock_table('cache');
-  db_query("UPDATE {cache} SET data = %b, created = %d, expire = %d, headers = '%s' WHERE cid = '%s'", $data, time(), $expire, $headers, $cid);
-  if (!db_affected_rows()) {
-    @db_query("INSERT INTO {cache} (cid, data, created, expire, headers) VALUES ('%s', %b, %d, %d, '%s')", $cid, $data, time(), $expire, $headers);
-  }
-  db_unlock_tables();
+// From chx's patch http://drupal.org/node/55516 http://drupal.org/files/issues/no_block.patch.txt
+  db_query_replace(
+    array("DELETE FROM {%s} WHERE cid = '%s'", $table, $cid),
+    array("INSERT INTO {%s} (cid, data, created, expire, headers) VALUES ('%s', %b, %d, %d, '%s')", $table, $cid, $data, time(), $expire, $headers)
+    );
 }
 
 /**
diff -ur drupal-4.7.4/includes/database.mysql.inc drupal-4.7.4-patched/includes/database.mysql.inc
--- drupal-4.7.4/includes/database.mysql.inc	2006-09-26 15:14:33.000000000 +0100
+++ drupal-4.7.4-patched/includes/database.mysql.inc	2006-12-19 01:14:53.000000000 +0000
@@ -196,21 +196,26 @@
 }
 
 /**
- * Return a new unique ID in the given sequence.
- *
- * For compatibility reasons, Drupal does not use auto-numbered fields in its
- * database tables. Instead, this function is used to return a new unique ID
- * of the type requested. If necessary, a new sequence with the given name
- * will be created.
+// From chx's patch http://drupal.org/node/55516 http://drupal.org/files/issues/no_block.patch.txt
+ * Return a new unique ID.
  */
 function db_next_id($name) {
-  $name = db_prefix_tables($name);
-  db_query('LOCK TABLES {sequences} WRITE');
-  $id = db_result(db_query("SELECT id FROM {sequences} WHERE name = '%s'", $name)) + 1;
-  db_query("REPLACE INTO {sequences} VALUES ('%s', %d)", $name, $id);
-  db_query('UNLOCK TABLES');
-
-  return $id;
+  // Prefix any curly-bracket "{table}" names
+   $name = db_prefix_tables($name);
+  // Assume initially that the sequence already exists.  Attempt to update it atomically.
+  // LAST_INSERT_ID lets us get its value later. IGNORE suppresses update failures.
+  db_query("UPDATE IGNORE {sequences} SET id=LAST_INSERT_ID(id + 1) WHERE name = '%s'", $name);
+  // Check whether that worked
+  if (!db_affected_rows()) {
+    // Updated failed, so the sequence doesn't exist yet.
+    // In either case, try to create a new sequence starting from zero
+    // IGNORE suppresses insert error if e.g. a concurrent process got there first.
+    db_query("INSERT IGNORE INTO {sequences} VALUES ('%s', %d)", $name, 0);
+    // Sequence now exists (unless some database error occurred to prevent it)
+    // Retry update, allowing for possible concurrent process. It should work this time.
+    db_query("UPDATE {sequences} SET id = LAST_INSERT_ID(id + 1) WHERE name = '%s'", $name);
+  }
+  return mysql_insert_id();
 }
 
 /**
@@ -308,7 +313,13 @@
   $tablename = array_pop($args);
   array_shift($args);
 
-  $query = preg_replace('/^SELECT/i', 'CREATE TEMPORARY TABLE '. $tablename .' SELECT', db_prefix_tables($query));
+// $user->sid is part of niosop's 
+// remove TEMPORARY TABLE patch at 
+// http://drupal.org/node/49644#comment-111742
+  global $user;
+
+  db_query("DROP TABLE IF EXISTS ".$tablename.$user->sid);
+  $query = preg_replace('/^SELECT/i', 'CREATE TABLE '.$tablename . $user->sid.' SELECT', db_prefix_tables($query));
   if (isset($args[0]) and is_array($args[0])) { // 'All arguments in one array' syntax
     $args = $args[0];
   }
@@ -364,6 +375,22 @@
   db_query('UNLOCK TABLES');
 }
 
+// From chx's patch http://drupal.org/node/55516 http://drupal.org/files/issues/no_block.patch.txt
+/**
+ * Perform a replace query.
+ *
+ * @param $delete
+ *   An array, where the first value is a query which deletes one row,
+ *   subsequent values are arguments. Same syntax as of db_query.
+ * @param
+ *   An array, where the first value is a query which inserts the new row,
+ *   subsequent values are arguments. Same syntax as of db_query.
+ */
+function db_query_replace($delete, $insert) {
+  $insert_query = array_shift($insert);
+  db_query(preg_replace('/^INSERT /', 'REPLACE ', $insert_query), $insert);
+}
+
 /**
  * @} End of "ingroup database".
  */
Only in drupal-4.7.4-patched/includes: database.mysql.inc~
diff -ur drupal-4.7.4/modules/search.module drupal-4.7.4-patched/modules/search.module
--- drupal-4.7.4/modules/search.module	2006-08-05 15:36:41.000000000 +0100
+++ drupal-4.7.4-patched/modules/search.module	2006-12-19 00:44:31.000000000 +0000
@@ -832,6 +832,10 @@
  * @ingroup search
  */
 function do_search($keywords, $type, $join1 = '', $where1 = '1', $arguments1 = array(), $select2 = 'i.relevance AS score', $join2 = '', $arguments2 = array(), $sort_parameters = 'ORDER BY score DESC') {
+// $user->sid is part of niosop's 
+// remove TEMPORARY TABLE patch at 
+// http://drupal.org/node/49644#comment-111742
+  global $user;
   $query = search_parse_query($keywords);
 
   if ($query[2] == '') {
@@ -848,7 +852,7 @@
   $result = db_query_temporary("SELECT i.type, i.sid, SUM(i.score * t.count) AS relevance, COUNT(*) AS matches FROM {search_index} i INNER JOIN {search_total} t ON i.word = t.word $join1 WHERE $conditions GROUP BY i.type, i.sid HAVING COUNT(*) >= %d", $arguments, 'temp_search_sids');
 
   // Calculate maximum relevance, to normalize it
-  $normalize = db_result(db_query('SELECT MAX(relevance) FROM temp_search_sids'));
+  $normalize = db_result(db_query('SELECT MAX(relevance) FROM temp_search_sids'.$user->sid));
   if (!$normalize) {
     return array();
   }
@@ -857,18 +861,22 @@
   // Second pass: only keep items that match the complicated keywords conditions (phrase search, negative keywords, ...)
   $conditions = '('. $query[0] .')';
   $arguments = array_merge($arguments2, $query[1]);
-  $result = db_query_temporary("SELECT i.type, i.sid, $select2 FROM temp_search_sids i INNER JOIN {search_dataset} d ON i.sid = d.sid AND i.type = d.type $join2 WHERE $conditions $sort_parameters", $arguments, 'temp_search_results');
-  if (($count = db_result(db_query('SELECT COUNT(*) FROM temp_search_results'))) == 0) {
+  $result = db_query_temporary("SELECT i.type, i.sid, $select2 FROM temp_search_sids".$user->sid." i INNER JOIN {search_dataset} d ON i.sid = d.sid AND i.type = d.type $join2 WHERE $conditions $sort_parameters", $arguments, 'temp_search_results');
+  if (($count = db_result(db_query('SELECT COUNT(*) FROM temp_search_results'.$user->sid))) == 0) {
+    db_query('DROP TABLE temp_search_results'.$user->sid);
+    db_query('DROP TABLE temp_search_sids'.$user->sid);
     return array();
   }
   $count_query = "SELECT $count";
 
   // Do actual search query
-  $result = pager_query("SELECT * FROM temp_search_results", 10, 0, $count_query);
+  $result = pager_query("SELECT * FROM temp_search_results".$user->sid, 10, 0, $count_query);
   $results = array();
   while ($item = db_fetch_object($result)) {
     $results[] = $item;
   }
+  db_query('DROP TABLE temp_search_results'.$user->sid);
+  db_query('DROP TABLE temp_search_sids'.$user->sid);
   return $results;
 }