diff --git a/wp-includes/class.wp-styles.php b/wp-includes/class.wp-styles.php
index 4a54b71676..927a7e7307 100644
--- a/wp-includes/class.wp-styles.php
+++ b/wp-includes/class.wp-styles.php
@@ -87,10 +87,11 @@ class WP_Styles extends WP_Dependencies {
 
 		if ( $this->do_concat ) {
 			$this->print_html .= $tag;
-			$this->print_html .= $this->print_inline_style( $handle, false );
+			if ( $inline_style = $this->print_inline_style( $handle, false ) )
+				$this->print_html .= sprintf( "<style type='text/css'>\n%s\n</style>\n", $inline_style );
 		} else {
 			echo $tag;
-			echo $this->print_inline_style( $handle, false );
+			$this->print_inline_style( $handle );
 		}
 
 		return true;
diff --git a/wp-includes/functions.wp-styles.php b/wp-includes/functions.wp-styles.php
index c3569927fb..d97667cf88 100644
--- a/wp-includes/functions.wp-styles.php
+++ b/wp-includes/functions.wp-styles.php
@@ -14,7 +14,7 @@
  * Passing an empty array to $handles prints the queue,
  * passing an array with one string prints that style,
  * and passing an array of strings prints those styles.
- * 
+ *
  * @see do_action() Calls 'wp_print_styles' hook.
  * @global WP_Styles $wp_styles The WP_Styles object for printing styles.
  *
@@ -71,6 +71,11 @@ function wp_add_inline_style( $handle, $data ) {
 		$wp_styles = new WP_Styles();
 	}
 
+	if ( false !== stripos( $data, '</style>' ) ) {
+		_doing_it_wrong( __FUNCTION__, 'Do not pass <style> tags to wp_add_inline_style()', '3.7' );
+		$data = trim( preg_replace( '#<style[^>]*>(.*)</style>#is', '$1', $data ) );
+	}
+
 	return $wp_styles->add_inline_style( $handle, $data );
 }