Index: branches/RC/core/install.php
===================================================================
diff -u -N -r10886 -r10924
--- branches/RC/core/install.php	(.../install.php)	(revision 10886)
+++ branches/RC/core/install.php	(.../install.php)	(revision 10924)
@@ -57,6 +57,7 @@
 		 */
 		var $steps = Array (
 			'fresh_install'		=>	Array ('check_paths', 'db_config', 'select_license', 'download_license', 'select_domain', 'root_password', 'choose_modules', 'post_config', 'select_theme', 'finish'),
+			'clean_reinstall'	=>	Array ('check_paths', 'clean_db', 'db_config', 'select_license', 'download_license', 'select_domain', 'root_password', 'choose_modules', 'post_config', 'select_theme', 'finish'),
 			'already_installed'	=>	Array ('check_paths', 'install_setup'),
 
 			'upgrade'			=>	Array ('check_paths', 'install_setup', 'upgrade_modules', 'finish'),
@@ -77,7 +78,7 @@
 		 *
 		 * @var Array
 		 */
-		var $skipApplicationSteps = Array ('check_paths', 'db_config', 'db_reconfig' /*, 'install_setup'*/); // remove install_setup when application will work separately from install
+		var $skipApplicationSteps = Array ('check_paths', 'clean_db', 'db_config', 'db_reconfig' /*, 'install_setup'*/); // remove install_setup when application will work separately from install
 
 		/**
 		 * Folders that should be writeable to continue installation. $1 - main writeable folder from config.php ("/system" by default)
@@ -242,6 +243,22 @@
 					}
 					break;
 
+				case 'clean_db':
+					// don't use Application, because all tables will be erased and it will crash
+					$sql = 'SELECT Path
+							FROM ' . TABLE_PREFIX . 'Modules';
+					$modules = $this->Conn->GetCol($sql);
+
+					foreach ($modules as $module_folder) {
+						$remove_file = '/' . $module_folder . 'install/remove_schema.sql';
+						if (file_exists(FULL_PATH . $remove_file)) {
+							$this->toolkit->RunSQL($remove_file);
+						}
+					}
+
+					$this->currentStep = $this->GetNextStep();
+					break;
+
 				case 'db_config':
 				case 'db_reconfig':
 					$fields = Array (