Index: wp-includes/script-loader.php
===================================================================
--- wp-includes/script-loader.php	(revision 19944)
+++ wp-includes/script-loader.php	(working copy)
@@ -575,8 +575,13 @@
 	if ( !is_a($wp_scripts, 'WP_Scripts') )
 		$wp_scripts = new WP_Scripts();
 
-	script_concat_settings();
-	$wp_scripts->do_concat = $concatenate_scripts;
+	if ( ! isset($concatenate_scripts) ) {
+		$wp_scripts->do_concat = defined('CONCATENATE_SCRIPTS') ? CONCATENATE_SCRIPTS : true;
+		if ( ! is_admin() || ( defined('SCRIPT_DEBUG') && SCRIPT_DEBUG ) )
+			$wp_scripts->do_concat = false;
+	} else
+		$wp_scripts->do_concat = $concatenate_scripts;
+
 	$wp_scripts->do_head_items();
 
 	if ( apply_filters('print_head_scripts', true) )
@@ -597,8 +602,13 @@
 	if ( !is_a($wp_scripts, 'WP_Scripts') )
 		return array(); // No need to run if not instantiated.
 
-	script_concat_settings();
-	$wp_scripts->do_concat = $concatenate_scripts;
+	if ( ! isset($concatenate_scripts) ) {
+		$wp_scripts->do_concat = defined('CONCATENATE_SCRIPTS') ? CONCATENATE_SCRIPTS : true;
+		if ( ! is_admin() || ( defined('SCRIPT_DEBUG') && SCRIPT_DEBUG ) )
+			$wp_scripts->do_concat = false;
+	} else
+		$wp_scripts->do_concat = $concatenate_scripts;
+
 	$wp_scripts->do_footer_items();
 
 	if ( apply_filters('print_footer_scripts', true) )
@@ -614,7 +624,15 @@
 function _print_scripts() {
 	global $wp_scripts, $compress_scripts;
 
-	$zip = $compress_scripts ? 1 : 0;
+	$compressed_output = ( ini_get('zlib.output_compression') || 'ob_gzhandler' == ini_get('output_handler') );
+
+	if ( ! isset($compress_scripts) ) {
+		$zip = defined('COMPRESS_SCRIPTS') ? COMPRESS_SCRIPTS : true;
+		if ( $zip && ( ! get_site_option('can_compress_scripts') || $compressed_output ) )
+			$zip = false;
+	} else
+		$zip = $compress_scripts;
+
 	if ( $zip && defined('ENFORCE_GZIP') && ENFORCE_GZIP )
 		$zip = 'gzip';
 
@@ -698,9 +716,22 @@
 	if ( !is_a($wp_styles, 'WP_Styles') )
 		$wp_styles = new WP_Styles();
 
-	script_concat_settings();
-	$wp_styles->do_concat = $concatenate_scripts;
-	$zip = $compress_css ? 1 : 0;
+	if ( ! isset($concatenate_scripts) ) {
+		$wp_styles->do_concat = defined('CONCATENATE_SCRIPTS') ? CONCATENATE_SCRIPTS : true;
+		if ( defined('SCRIPT_DEBUG') && SCRIPT_DEBUG )
+			$wp_styles->do_concat = false;
+	} else
+		$wp_styles->do_concat = $concatenate_scripts;
+
+	$compressed_output = ( ini_get('zlib.output_compression') || 'ob_gzhandler' == ini_get('output_handler') );
+
+	if ( ! isset($compress_css) ) {
+		$zip = defined('COMPRESS_CSS') ? COMPRESS_CSS : true;
+		if ( $compress_css && ( ! get_site_option('can_compress_scripts') || $compressed_output ) )
+			$zip = false;
+	} else
+		$zip = $compress_css;
+
 	if ( $zip && defined('ENFORCE_GZIP') && ENFORCE_GZIP )
 		$zip = 'gzip';
 
@@ -724,7 +755,13 @@
 	if ( !is_a($wp_styles, 'WP_Styles') )
 		return;
 
-	$wp_styles->do_concat = $concatenate_scripts;
+	if ( ! isset($concatenate_scripts) ) {
+		$wp_styles->do_concat = defined('CONCATENATE_SCRIPTS') ? CONCATENATE_SCRIPTS : true;
+		if ( !is_admin() || ( defined('SCRIPT_DEBUG') && SCRIPT_DEBUG ) )
+			$wp_styles->do_concat = false;
+	} else
+		$wp_styles->do_concat = $concatenate_scripts;
+
 	$wp_styles->do_footer_items();
 
 	if ( apply_filters('print_late_styles', true) )
@@ -740,7 +777,15 @@
 function _print_styles() {
 	global $wp_styles, $compress_css;
 
-	$zip = $compress_css ? 1 : 0;
+	$compressed_output = ( ini_get('zlib.output_compression') || 'ob_gzhandler' == ini_get('output_handler') );
+
+	if ( ! isset($compress_css) ) {
+		$zip = defined('COMPRESS_CSS') ? COMPRESS_CSS : true;
+		if ( $zip && ( ! get_site_option('can_compress_scripts') || $compressed_output ) )
+			$zip = false;
+	} else
+		$zip = $compress_css;
+
 	if ( $zip && defined('ENFORCE_GZIP') && ENFORCE_GZIP )
 		$zip = 'gzip';
 
@@ -761,35 +806,6 @@
 		echo $wp_styles->print_html;
 }
 
-/**
- * Determine the concatenation and compression settings for scripts and styles.
- *
- * @since 2.8
- */
-function script_concat_settings() {
-	global $concatenate_scripts, $compress_scripts, $compress_css;
-
-	$compressed_output = ( ini_get('zlib.output_compression') || 'ob_gzhandler' == ini_get('output_handler') );
-
-	if ( ! isset($concatenate_scripts) ) {
-		$concatenate_scripts = defined('CONCATENATE_SCRIPTS') ? CONCATENATE_SCRIPTS : true;
-		if ( ! is_admin() || ( defined('SCRIPT_DEBUG') && SCRIPT_DEBUG ) )
-			$concatenate_scripts = false;
-	}
-
-	if ( ! isset($compress_scripts) ) {
-		$compress_scripts = defined('COMPRESS_SCRIPTS') ? COMPRESS_SCRIPTS : true;
-		if ( $compress_scripts && ( ! get_site_option('can_compress_scripts') || $compressed_output ) )
-			$compress_scripts = false;
-	}
-
-	if ( ! isset($compress_css) ) {
-		$compress_css = defined('COMPRESS_CSS') ? COMPRESS_CSS : true;
-		if ( $compress_css && ( ! get_site_option('can_compress_scripts') || $compressed_output ) )
-			$compress_css = false;
-	}
-}
-
 add_action( 'wp_default_scripts', 'wp_default_scripts' );
 add_filter( 'wp_print_scripts', 'wp_just_in_time_script_localization' );
 add_filter( 'print_scripts_array', 'wp_prototype_before_jquery' );
Index: wp-includes/class-wp-editor.php
===================================================================
--- wp-includes/class-wp-editor.php	(revision 19944)
+++ wp-includes/class-wp-editor.php	(working copy)
@@ -257,7 +257,6 @@
 
 				self::$plugins = $plugins;
 				self::$ext_plugins = $ext_plugins;
-
 				/*
 				translators: These languages show up in the spellchecker drop-down menu, in the order specified, and with the first
 				language listed being the default language. They must be comma-separated and take the format of name=code, where name
@@ -481,9 +480,20 @@
 		$version = 'ver=' . $tinymce_version;
 		$tmce_on = !empty(self::$mce_settings);
 
-		if ( ! isset($concatenate_scripts) )
-			script_concat_settings();
+		$compressed_output = ( ini_get('zlib.output_compression') || 'ob_gzhandler' == ini_get('output_handler') );
 
+		if ( ! isset($compress_scripts) ) {
+			$compress_scripts = defined('COMPRESS_SCRIPTS') ? COMPRESS_SCRIPTS : true;
+			if ( $compress_scripts && ( ! get_site_option('can_compress_scripts') || $compressed_output ) )
+				$compress_scripts = false;
+		}
+		
+		if ( ! isset($concatenate_scripts) ) {
+			$concatenate_scripts = defined('CONCATENATE_SCRIPTS') ? CONCATENATE_SCRIPTS : true;
+			if ( ! is_admin() || ( defined('SCRIPT_DEBUG') && SCRIPT_DEBUG ) )
+				$concatenate_scripts = false;
+		}
+		
 		$compressed = $compress_scripts && $concatenate_scripts && isset($_SERVER['HTTP_ACCEPT_ENCODING'])
 			&& false !== stripos($_SERVER['HTTP_ACCEPT_ENCODING'], 'gzip');
 
@@ -517,13 +527,15 @@
 			'language' => self::$mce_locale
 		);
 
+		$suffix = $concatenate_scripts ? '' : '_dev';
+
 		do_action('before_wp_tiny_mce', self::$mce_settings);
 ?>
 
 	<script type="text/javascript">
 		tinyMCEPreInit = {
 			base : "<?php echo self::$baseurl; ?>",
-			suffix : "",
+			suffix : '<?php echo $suffix; ?>',
 			query : "<?php echo $version; ?>",
 			mceInit : <?php echo $mceInit; ?>,
 			qtInit : <?php echo $qtInit; ?>,
