diff --git a/readme.txt b/readme.txt
index d292c93..ffa8f50 100644
--- a/readme.txt
+++ b/readme.txt
@@ -3,8 +3,8 @@ Contributors: cadeyrn
 Donate link: https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=XU3DG7LLA76WC
 Tags: cache, page cache, full page cache, nginx, memcached, apc, speed
 Requires at least: 3.0
-Tested up to: 3.9.1
-Stable tag: 1.5.0
+Tested up to: 4.0
+Stable tag: 1.6.0
 License: GPLv3
 License URI: http://www.gnu.org/licenses/gpl-3.0.html
 
@@ -17,14 +17,14 @@ It can be configured to join forces with [NGiNX](http://NGiNX.org "NGiNX")'s bui
 = Features: =
 * Wordpress Network support
   * fully supported domain/subdomain based WordPress Networks on per site setup as well
-  * will work in Network Enabled mode only for subdirectory based Multisites ( no per site setting possibility )
-* supports variable backends
+  * will work in Network Enabled mode only for subdirectory based Multisites ( per site settings will not work in this case )
+* supports various backends
   * memcached with [PHP Memcached](http://php.net/manual/en/book.memcached.php "Memcached")
   * memcached with [PHP Memcache](http://php.net/manual/en/book.memcache.php "Memcache")
   * [APC](http://php.net/manual/en/book.apc.php "APC")
   * [APCu](http://pecl.php.net/package/APCu "APC User Cache")
   * [Xcache](http://xcache.lighttpd.net/ "Xcache") - not stable yet, volunteer testers required!
-* cache exclude possibilities ( home, feeds, archieves, pages, singles )
+* cache exclude options ( home, feeds, archieves, pages, singles; regex based url exclusion )
 * (optional) cache for logged-in users
 * 404 caching
 * canonical redirects caching
@@ -43,6 +43,8 @@ Many thanks for donations, contributors, supporters, testers & bug reporters:
 * [Mark Costlow](mailto:cheeks@swcp.com "Mark Costlow")
 * [Jason Miller](mailto:jason@redconfetti.com "Jason Miller")
 * [Dave Clark](https://github.com/dkcwd "Dave Clark")
+* Miguel Clara
+* [plescheff](https://github.com/plescheff)
 
 == Installation ==
 
@@ -98,6 +100,29 @@ Please post feature requests to [WP-FFPC feature request topic](http://wordpress
 
 == Changelog ==
 
+Version numbering logic:
+
+* every A. indicates BIG changes.
+* every .B version indicates new features.
+* every ..C indicates bugfixes for A.B version.
+
+= 1.6.0 =
+*2014-05-30*
+
+What's new:
+
+* added functionality to exclude regex urls, contribution from [plescheff](https://github.com/plescheff/wp-ffpc/commit/3c875ad4fe1e083d3968421dd83b9c179c686649)
+* added functionality to include "?" containing URL
+
+What's fixed:
+
+* some warning messages removed in case there's not a single backend installed when the plugin is activated
+
+Under the hood:
+
+* major changes to the abstract wp-common class for better interoperability between my plugins
+
+
 = 1.5.0 =
 *2014-05-30*
 
diff --git a/wp-common b/wp-common
index 2dd92a6..d84ff21 160000
--- a/wp-common
+++ b/wp-common
@@ -1 +1 @@
-Subproject commit 2dd92a681f986a6637550a2640c697be39399de9
+Subproject commit d84ff213cd944c22a6a440d6faba502abd1da774
diff --git a/wp-ffpc-acache.php b/wp-ffpc-acache.php
index 024d253..904f346 100644
--- a/wp-ffpc-acache.php
+++ b/wp-ffpc-acache.php
@@ -26,7 +26,7 @@ if (defined('SID') && SID != '')
 $wp_ffpc_uri = $_SERVER['REQUEST_URI'];
 
 /* no cache for uri with query strings, things usually go bad that way */
-if ( stripos($wp_ffpc_uri, '?') !== false)
+if ( isset($wp_ffpc_config['nocache_dyn']) && !empty($wp_ffpc_config['nocache_dyn']) && stripos($wp_ffpc_uri, '?') !== false ) {
 	return false;
 
 /* no cache for pages starting with /wp- like WP admin */
@@ -67,6 +67,14 @@ if ( isset($wp_ffpc_config['nocache_cookies']) && !empty($wp_ffpc_config['nocach
 	}
 }
 
+/* no cache for excluded URL patterns */
+if ( isset($wp_ffpc_config['nocache_url']) && trim($wp_ffpc_config['nocache_url']) ) {
+	$pattern = sprintf('#%s#', trim($wp_ffpc_config['nocache_url']));
+	if ( preg_match($pattern, $wp_ffpc_uri) ) {
+		return false;
+	}
+}
+
 /* canonical redirect storage */
 $wp_ffpc_redirect = null;
 /* fires up the backend storage array with current config */
@@ -254,7 +262,7 @@ function wp_ffpc_callback( $buffer ) {
 		}
 	}
 
-	if ( is_404() ) 
+	if ( is_404() )
 		$meta['status'] = 404;
 
 	/* redirect page */
diff --git a/wp-ffpc-backend.php b/wp-ffpc-backend.php
index dbc4be6..2d03186 100644
--- a/wp-ffpc-backend.php
+++ b/wp-ffpc-backend.php
@@ -520,7 +520,7 @@ class WP_FFPC_Backend {
 		}
 
 		/* verify apcu is working */
-		if ( apcu_cache_info("user",true) ) {
+		if ( apcu_cache_info("user") ) {
 			$this->log (  __translate__('backend OK', $this->plugin_constant ) );
 			$this->alive = true;
 		}
@@ -606,6 +606,14 @@ class WP_FFPC_Backend {
 			return false;
 		}
 
+		$xcache_admin = ini_get ( 'xcache.admin.user' );
+		$xcache_pass = ini_get ( 'xcache.admin.pass' );
+
+		if ( empty( $xcache_admin ) || empty( $xcache_pass ) ) {
+			$this->log (  __translate__('XCACHE xcache.admin.user or xcache.admin.pass is not set in php.ini. Please set them, otherwise the use cache part of xcache is not accessible.', $this->plugin_constant ) );
+			return false;
+		}
+
 		/* verify apc is working */
 		$info = xcache_info();
 		if ( !empty( $info )) {
@@ -716,7 +724,7 @@ class WP_FFPC_Backend {
 			$this->connection->setOption( Memcached::OPT_COMPRESSION , false );
 			$this->connection->setOption( Memcached::OPT_BINARY_PROTOCOL , true );
 
-			if ( version_compare( phpversion( 'memcached' ) , '2.0.0', '>=' ) && ini_get( 'memcached.use_sasl' ) == 1 ) {
+			if ( version_compare( phpversion( 'memcached' ) , '2.0.0', '>=' ) && ini_get( 'memcached.use_sasl' ) == 1 && isset($this->options['authpass']) && !empty($this->options['authpass']) && isset($this->options['authuser']) && !empty($this->options['authuser']) ) {
 				$this->connection->setSaslAuthData ( $this->options['authuser'], $this->options['authpass']);
 			}
 		}
diff --git a/wp-ffpc-class.php b/wp-ffpc-class.php
index 3961d77..2e0b6e6 100644
--- a/wp-ffpc-class.php
+++ b/wp-ffpc-class.php
@@ -3,9 +3,9 @@
 if ( ! class_exists( 'WP_FFPC' ) ) :
 
 /* get the plugin abstract class*/
-include_once ( 'wp-common/plugin_abstract.php' );
+include_once ( dirname(__FILE__) . '/wp-common/plugin_abstract.php' );
 /* get the common functions class*/
-include_once ( 'wp-ffpc-backend.php' );
+include_once ( dirname(__FILE__) .'/wp-ffpc-backend.php' );
 
 /**
  * main wp-ffpc class
@@ -63,6 +63,20 @@ class WP_FFPC extends PluginAbstract {
 	private $scheduled = false;
 	private $errors = array();
 
+	/**
+	 *
+	 */
+	public function plugin_post_construct () {
+		$this->plugin_url = plugin_dir_url( __FILE__ );
+		$this->plugin_dir = plugin_dir_path( __FILE__ );
+
+		$this->common_url = $this->plugin_url . self::common_slug;
+		$this->common_dir = $this->plugin_dir . self::common_slug;
+
+		$this->admin_css_handle = $this->plugin_constant . '-admin-css';
+		$this->admin_css_url = $this->common_url . 'wp-admin.css';
+	}
+
 	/**
 	 * init hook function runs before admin panel hook, themeing and options read
 	 */
@@ -272,12 +286,11 @@ class WP_FFPC extends PluginAbstract {
 	 */
 	public function plugin_extend_admin_init () {
 		/* save parameter updates, if there are any */
-		if ( isset( $_POST[ $this->button_flush ] ) ) {
-
+		if ( isset( $_POST[ $this->button_flush ] ) && check_admin_referer ( $this->plugin_constant ) ) {
 			/* remove precache log entry */
-			$this->_delete_option( self::precache_log  );
+			$this->utils->_delete_option( self::precache_log  );
 			/* remove precache timestamp entry */
-			$this->_delete_option( self::precache_timestamp );
+			$this->utils->_delete_option( self::precache_timestamp );
 
 			/* remove precache logfile */
 			if ( @file_exists ( $this->precache_logfile ) ) {
@@ -296,8 +309,7 @@ class WP_FFPC extends PluginAbstract {
 		}
 
 		/* save parameter updates, if there are any */
-		if ( isset( $_POST[ $this->button_precache ] ) ) {
-
+		if ( isset( $_POST[ $this->button_precache ] ) && check_admin_referer ( $this->plugin_constant ) ) {
 			/* is no shell function is possible, fail */
 			if ( $this->shell_function == false ) {
 				$this->status = 5;
@@ -407,15 +419,17 @@ class WP_FFPC extends PluginAbstract {
 
 				/* we need to go through all servers */
 				$servers = $this->backend->status();
-				foreach ( $servers as $server_string => $status ) {
-					echo $server_string ." => ";
+				if ( is_array( $servers ) && !empty ( $servers ) ) {
+					foreach ( $servers as $server_string => $status ) {
+						echo $server_string ." => ";
 
-					if ( $status == 0 )
-						_e ( '<span class="error-msg">down</span><br />', $this->plugin_constant );
-					elseif ( ( $this->options['cache_type'] == 'memcache' && $status > 0 )  || $status == 1 )
-						_e ( '<span class="ok-msg">up & running</span><br />', $this->plugin_constant );
-					else
-						_e ( '<span class="error-msg">unknown, please try re-saving settings!</span><br />', $this->plugin_constant );
+						if ( $status == 0 )
+							_e ( '<span class="error-msg">down</span><br />', $this->plugin_constant );
+						elseif ( ( $this->options['cache_type'] == 'memcache' && $status > 0 )  || $status == 1 )
+							_e ( '<span class="ok-msg">up & running</span><br />', $this->plugin_constant );
+						else
+							_e ( '<span class="error-msg">unknown, please try re-saving settings!</span><br />', $this->plugin_constant );
+					}
 				}
 
 				?></p><?php
@@ -423,6 +437,7 @@ class WP_FFPC extends PluginAbstract {
 		</div>
 		<form autocomplete="off" method="post" action="#" id="<?php echo $this->plugin_constant ?>-settings" class="plugin-admin">
 
+			<?php wp_nonce_field( $this->plugin_constant ); ?>
 			<ul class="tabs">
 				<li><a href="#<?php echo $this->plugin_constant ?>-type" class="wp-switch-editor"><?php _e( 'Cache type', $this->plugin_constant ); ?></a></li>
 				<li><a href="#<?php echo $this->plugin_constant ?>-debug" class="wp-switch-editor"><?php _e( 'Debug & in-depth', $this->plugin_constant ); ?></a></li>
@@ -600,6 +615,26 @@ class WP_FFPC extends PluginAbstract {
 					<input type="text" name="nocache_cookies" id="nocache_cookies" value="<?php if(isset( $this->options['nocache_cookies'] ) ) echo $this->options['nocache_cookies']; ?>" />
 					<span class="description"><?php _e('Exclude cookies names starting with this from caching. Separate multiple cookies names with commas.<br />If you are caching with nginx, you should update your nginx configuration and reload nginx after changing this value.', $this->plugin_constant); ?></span>
 				</dd>
+
+				<dt>
+					<label for="nocache_dyn"><?php _e("Don't cache dynamic requests", $this->plugin_constant); ?></label>
+				</dt>
+				<dd>
+					<input type="checkbox" name="nocache_dyn" id="nocache_dyn" value="1" <?php checked($this->options['nocache_dyn'],true); ?> />
+					<span class="description"><?php _e('Exclude every URL with "?" in it.', $this->plugin_constant); ?></span>
+				</dd>
+
+				<dt>
+					<label for="nocache_url"><?php _e("Don't cache following URL paths - use with caution!", $this->plugin_constant); ?></label>
+				</dt>
+				<dd>
+					<textarea name="nocache_url" id="nocache_url" rows="3" cols="100" class="large-text code"><?php
+						if( isset( $this->options['nocache_url'] ) ) {
+							echo $this->options['nocache_url'];
+						}
+					?></textarea>
+					<span class="description"><?php _e('Regular expressions use you must! e.g. <em>pattern1|pattern2|etc</em>', $this->plugin_constant); ?></span>
+				</dd>
 			</dl>
 			</fieldset>
 
@@ -717,6 +752,8 @@ class WP_FFPC extends PluginAbstract {
 
 		<form method="post" action="#" id="<?php echo $this->plugin_constant ?>-commands" class="plugin-admin" style="padding-top:2em;">
 
+			<?php wp_nonce_field( $this->plugin_constant ); ?>
+
 			<ul class="tabs">
 				<li><a href="#<?php echo $this->plugin_constant ?>-precache" class="wp-switch-editor"><?php _e( 'Precache', $this->plugin_constant ); ?></a></li>
 				<li><a href="#<?php echo $this->plugin_constant ?>-flush" class="wp-switch-editor"><?php _e( 'Empty cache', $this->plugin_constant ); ?></a></li>
@@ -824,9 +861,8 @@ class WP_FFPC extends PluginAbstract {
 	 *
 	 */
 	public function plugin_options_migrate( &$options ) {
-		$migrated = false;
 
-		if ( version_compare ( $options['version'] , $this->plugin_version , '<' ) ) {
+		if ( version_compare ( $options['version'] , $this->plugin_version, '<' ) ) {
 			/* cleanup possible leftover files from previous versions */
 			$check = array ( 'advanced-cache.php', 'nginx-sample.conf', 'wp-ffpc.admin.css', 'wp-ffpc-common.php' );
 			foreach ( $check as $fname ) {
@@ -844,37 +880,26 @@ class WP_FFPC extends PluginAbstract {
 
 				if ( empty ( $options ) && array_key_exists ( $this->global_config_key, $try ) ) {
 					$options = $try [ $this->global_config_key ];
-					$migrated = true;
 				}
 				elseif ( empty ( $options ) && array_key_exists ( 'host', $try ) ) {
 					$options = $try;
-					$migrated = true;
 				}
 			 }
 
 			/* updating from version <= 0.4.x */
 			if ( !empty ( $options['host'] ) ) {
 				$options['hosts'] = $options['host'] . ':' . $options['port'];
-				$migrated = true;
 			}
 			/* migrating from version 0.6.x */
 			elseif ( is_array ( $options ) && array_key_exists ( $this->global_config_key , $options ) ) {
 				$options = $options[ $this->global_config_key ];
-				$migrated = true;
-			}
-			/* migrating from something, drop previous config */
-			else {
-				$options = array();
 			}
 
-			if ( $migrated ) {
-				/* renamed options */
-				if ( isset ( $options['syslog'] ) )
-					$options['log'] = $options['syslog'];
-				if ( isset ( $options['debug'] ) )
+			/* renamed options */
+			if ( isset ( $options['syslog'] ) )
+				$options['log'] = $options['syslog'];
+			if ( isset ( $options['debug'] ) )
 				$options['response_header'] = $options['debug'];
-			}
-
 		}
 	}
 
@@ -1146,7 +1171,7 @@ class WP_FFPC extends PluginAbstract {
 			}
 
 			/* in case the bloglinks are relative links add the base url, site specific */
-			$baseurl = empty( $url ) ? $this->_site_url() : $url;
+			$baseurl = empty( $url ) ? $this->utils->_site_url() : $url;
 			if ( !strstr( $permalink, $baseurl ) ) {
 				$permalink = $baseurl . $permalink;
 			}
diff --git a/wp-ffpc.php b/wp-ffpc.php
index 975ccf8..d5285eb 100644
--- a/wp-ffpc.php
+++ b/wp-ffpc.php
@@ -1,9 +1,9 @@
 <?php
 /*
 Plugin Name: WP-FFPC
-Plugin URI: http://petermolnar.eu/wordpress/wp-ffpc
-Description: WordPress cache plugin for memcached & nginx - unbeatable speed
-Version: 1.5.0
+Plugin URI: https://github.com/petermolnar/wp-ffpc
+Description: WordPress in-memory full page cache plugin
+Version: 1.6.0
 Author: Peter Molnar <hello@petermolnar.eu>
 Author URI: http://petermolnar.eu/
 License: GPLv3
@@ -45,6 +45,8 @@ $wp_ffpc_defaults = array (
 	'nocache_single' => false,
 	'nocache_page' => false,
 	'nocache_cookies' => false,
+	'nocache_dyn' => true,
+	'nocache_url' => '',
 	'persistent' => false,
 	'response_header' => false,
 	'generate_time' => false,