Index: install/install_schema.sql
===================================================================
--- install/install_schema.sql	(revision 15230)
+++ install/install_schema.sql	(working copy)
@@ -675,16 +675,16 @@
 );
 
 CREATE TABLE SlowSqlCapture (
-  CaptureId int(10) unsigned NOT NULL auto_increment,
+  CaptureId int(10) unsigned NOT NULL AUTO_INCREMENT,
   TemplateNames text,
-  Hits int(10) unsigned NOT NULL default '0',
-  LastHit int(11) NOT NULL default '0',
+  Hits int(10) unsigned NOT NULL DEFAULT '0',
+  LastHit int(11) NOT NULL DEFAULT '0',
   SqlQuery text,
-  TimeMin decimal(40,20) unsigned NOT NULL default '0.00000000000000000000',
-  TimeAvg decimal(40,20) unsigned NOT NULL default '0.00000000000000000000',
-  TimeMax decimal(40,20) unsigned NOT NULL default '0.00000000000000000000',
-  QueryCrc int(11) NOT NULL default '0',
-  PRIMARY KEY  (CaptureId),
+  TimeMin decimal(40,20) unsigned NOT NULL DEFAULT '0.00000000000000000000',
+  TimeAvg decimal(40,20) unsigned NOT NULL DEFAULT '0.00000000000000000000',
+  TimeMax decimal(40,20) unsigned NOT NULL DEFAULT '0.00000000000000000000',
+  QueryCrc bigint(11) NOT NULL DEFAULT '0',
+  PRIMARY KEY (CaptureId),
   KEY Hits (Hits),
   KEY LastHit (LastHit),
   KEY TimeMin (TimeMin),
@@ -1015,7 +1015,7 @@
 CREATE TABLE ImportCache (
   CacheId int(11) NOT NULL AUTO_INCREMENT,
   CacheName varchar(255) NOT NULL DEFAULT '',
-  VarName int(11) NOT NULL DEFAULT '0',
+  VarName bigint(11) NOT NULL DEFAULT '0',
   VarValue text,
   PRIMARY KEY (CacheId),
   KEY CacheName (CacheName),
@@ -1065,7 +1065,7 @@
 
 CREATE TABLE PageContent (
   PageContentId int(11) NOT NULL AUTO_INCREMENT,
-  ContentNum int(11) NOT NULL DEFAULT '0',
+  ContentNum bigint(11) NOT NULL DEFAULT '0',
   PageId int(11) NOT NULL DEFAULT '0',
   RevisionId int(11) NOT NULL,
   l1_Content text,
@@ -1231,7 +1231,7 @@
   UrlId int(11) NOT NULL AUTO_INCREMENT,
   Url varchar(255) NOT NULL DEFAULT '',
   DomainId int(11) NOT NULL DEFAULT '0',
-  `Hash` int(11) NOT NULL DEFAULT '0',
+  `Hash` bigint(11) NOT NULL DEFAULT '0',
   Prefixes varchar(255) NOT NULL DEFAULT '',
   ParsedVars text,
   Cached int(10) unsigned DEFAULT NULL,
Index: install/upgrades.sql
===================================================================
--- install/upgrades.sql	(revision 15235)
+++ install/upgrades.sql	(working copy)
@@ -2689,3 +2689,23 @@
 INSERT INTO Permissions VALUES (DEFAULT, 'in-portal:item_filters.add', 11, 1, 1, 0);
 INSERT INTO Permissions VALUES (DEFAULT, 'in-portal:item_filters.edit', 11, 1, 1, 0);
 INSERT INTO Permissions VALUES (DEFAULT, 'in-portal:item_filters.delete', 11, 1, 1, 0);
+
+ALTER TABLE SlowSqlCapture CHANGE QueryCrc QueryCrc BIGINT(11) NOT NULL DEFAULT '0';
+UPDATE SlowSqlCapture
+SET QueryCrc = CAST((QueryCrc & 0xFFFFFFFF) AS UNSIGNED INTEGER)
+WHERE QueryCrc < 0;
+
+ALTER TABLE ImportCache CHANGE VarName VarName BIGINT(11) NOT NULL DEFAULT '0';
+UPDATE ImportCache
+SET VarName = CAST((VarName & 0xFFFFFFFF) AS UNSIGNED INTEGER)
+WHERE VarName < 0;
+
+ALTER TABLE PageContent CHANGE ContentNum ContentNum BIGINT(11) NOT NULL DEFAULT '0';
+UPDATE PageContent
+SET ContentNum = CAST((ContentNum & 0xFFFFFFFF) AS UNSIGNED INTEGER)
+WHERE ContentNum < 0;
+
+ALTER TABLE CachedUrls CHANGE Hash Hash BIGINT(11) NOT NULL DEFAULT '0';
+UPDATE CachedUrls
+SET Hash = CAST((Hash & 0xFFFFFFFF) AS UNSIGNED INTEGER)
+WHERE Hash < 0;
Index: kernel/application.php
===================================================================
--- kernel/application.php	(revision 15239)
+++ kernel/application.php	(working copy)
@@ -1283,7 +1283,7 @@
 	 */
 	public function logSlowQuery($slow_sql, $time)
 	{
-		$query_crc = crc32($slow_sql);
+		$query_crc = kUtil::crc32($slow_sql);
 
 		$sql = 'SELECT *
 				FROM ' . TABLE_PREFIX . 'SlowSqlCapture
Index: kernel/globals.php
===================================================================
--- kernel/globals.php	(revision 15226)
+++ kernel/globals.php	(working copy)
@@ -677,6 +677,17 @@
 			return $path;
 		}
 	}
+
+	/**
+	 * Calculates the crc32 polynomial of a string (always positive number)
+	 *
+	 * @param string $str
+	 * @return int
+	 */
+	public static function crc32($str)
+	{
+		return sprintf('%u', crc32($str));
+	}
 }
 
 /**
Index: kernel/managers/rewrite_url_processor.php
===================================================================
--- kernel/managers/rewrite_url_processor.php	(revision 15226)
+++ kernel/managers/rewrite_url_processor.php	(working copy)
@@ -189,7 +189,7 @@
 
 		$sql = 'SELECT *
 				FROM ' . TABLE_PREFIX . 'CachedUrls
-				WHERE Hash = ' . crc32($url) . ' AND DomainId = ' . (int)$this->Application->siteDomainField('DomainId');
+				WHERE Hash = ' . kUtil::crc32($url) . ' AND DomainId = ' . (int)$this->Application->siteDomainField('DomainId');
 		$data = $this->Conn->GetRow($sql);
 
 		if ($data) {
@@ -261,7 +261,7 @@
 
 		$fields_hash = Array (
 			'Url' => $url,
-			'Hash' => crc32($url),
+			'Hash' => kUtil::crc32($url),
 			'DomainId' => (int)$this->Application->siteDomainField('DomainId'),
 			'Prefixes' => $prefixes ? '|' . implode('|', $prefixes) . '|' : '',
 			'ParsedVars' => serialize($data),
Index: units/categories/categories_tag_processor.php
===================================================================
--- units/categories/categories_tag_processor.php	(revision 15165)
+++ units/categories/categories_tag_processor.php	(working copy)
@@ -1164,7 +1164,7 @@
 			$name = getArrayValue($params, 'name');
 
 			if ( $name ) {
-				$num = crc32($name);
+				$num = kUtil::crc32($name);
 			}
 		}
 
Index: units/helpers/cat_dbitem_export_helper.php
===================================================================
--- units/helpers/cat_dbitem_export_helper.php	(revision 15241)
+++ units/helpers/cat_dbitem_export_helper.php	(working copy)
@@ -115,34 +115,38 @@
 
 		function storeCache($cache_types)
 		{
+			$fields_hash = Array ();
 			$cache_types = explode(',', $cache_types);
 
-			$values_sql = '';
 			foreach ($cache_types as $cache_type) {
-				$sql_mask = '('.$this->Conn->qstr($cache_type).',%s,%s),';
+				$fields_hash = Array ('CacheName' => $cache_type);
 				$cache = getArrayValue($this->cacheStatus, $cache_type);
-				if (!$cache) $cache = Array();
+
+				if ( !$cache ) {
+					$cache = Array ();
+				}
+
 				foreach ($cache as $var_name => $cache_status) {
-					$var_value = $this->cache[$cache_type][$var_name];
-					$values_sql .= sprintf($sql_mask, $this->Conn->qstr($var_name), $this->Conn->qstr($var_value) );
+					$fields_hash['VarName'] = $var_name;
+					$fields_hash['VarValue'] = $this->cache[$cache_type][$var_name];
+
+					$this->Conn->doInsert($fields_hash, $this->cacheTable, 'INSERT', false);
 				}
 			}
 
-			$values_sql = substr($values_sql, 0, -1);
-
-			if ($values_sql) {
-				$sql = 'INSERT INTO '.$this->cacheTable.'(`CacheName`,`VarName`,`VarValue`) VALUES '.$values_sql;
-				$this->Conn->Query($sql);
+			if ( isset($fields_hash['VarName']) ) {
+				$this->Conn->doInsert($fields_hash, $this->cacheTable, 'INSERT');
 			}
-
 		}
 
 		function loadCache()
 		{
-			$sql = 'SELECT * FROM '.$this->cacheTable;
-			$records = $this->Conn->Query($sql);
+			$this->cache = Array ();
 
-			$this->cache = Array();
+			$sql = 'SELECT *
+					FROM ' . $this->cacheTable;
+			$records = $this->Conn->GetIterator($sql);
+
 			foreach ($records as $record) {
 				$this->addToCache($record['CacheName'], $record['VarName'], $record['VarValue'], false);
 			}
@@ -815,7 +819,7 @@
 
 			foreach ($this->curItem->CategoryPath as $category_index => $category_name) {
 				if (!$category_name) continue;
-				$category_key = crc32( implode(':', array_slice($this->curItem->CategoryPath, 0, $category_index + 1) ) );
+				$category_key = kUtil::crc32( implode(':', array_slice($this->curItem->CategoryPath, 0, $category_index + 1) ) );
 
 				$category_id = $this->getFromCache('category_names', $category_key);
 				if ($category_id === false) {
@@ -915,7 +919,7 @@
 					}
 					$where_clause = substr($where_clause, 0, -5);
 
-					$item_id = $this->getFromCache('new_ids', crc32($where_clause));
+					$item_id = $this->getFromCache('new_ids', kUtil::crc32($where_clause));
 					if (!$item_id) {
 						if ($this->exportOptions['CheckDuplicatesMethod'] == 2) {
 							// by other fields
@@ -963,7 +967,7 @@
 
 			if ($load_keys && ($save_method == 'Create') && $this->exportOptions['ReplaceDuplicates']) {
 				// map new id to old id
-				$this->addToCache('new_ids', crc32($where_clause), $this->curItem->GetID() );
+				$this->addToCache('new_ids', kUtil::crc32($where_clause), $this->curItem->GetID() );
 			}
 
 			// assign item to categories