Index: src/wp-admin/includes/ajax-actions.php
===================================================================
--- src/wp-admin/includes/ajax-actions.php	(revision 42413)
+++ src/wp-admin/includes/ajax-actions.php	(working copy)
@@ -1184,7 +1184,7 @@
 	if ( empty( $post->post_status ) ) {
 		wp_die( 1 );
 	} elseif ( in_array( $post->post_status, array( 'draft', 'pending', 'trash' ) ) ) {
-		wp_die( __( 'ERROR: you are replying to a comment on a draft post.' ) );
+		wp_die( __( 'ERROR: You are replying to a comment on a draft post.' ) );
 	}
 
 	$user = wp_get_current_user();
@@ -1210,7 +1210,7 @@
 	}
 
 	if ( '' == $comment_content ) {
-		wp_die( __( 'ERROR: please type a comment.' ) );
+		wp_die( __( 'ERROR: Please type a comment.' ) );
 	}
 
 	$comment_parent = 0;
@@ -1306,7 +1306,7 @@
 	}
 
 	if ( '' == $_POST['content'] ) {
-		wp_die( __( 'ERROR: please type a comment.' ) );
+		wp_die( __( 'ERROR: Please type a comment.' ) );
 	}
 
 	if ( isset( $_POST['status'] ) ) {
Index: src/wp-admin/options.php
===================================================================
--- src/wp-admin/options.php	(revision 42413)
+++ src/wp-admin/options.php	(working copy)
@@ -156,7 +156,7 @@
 	}
 
 	if ( ! isset( $whitelist_options[ $option_page ] ) ) {
-		wp_die( __( '<strong>ERROR</strong>: options page not found.' ) );
+		wp_die( __( '<strong>ERROR</strong>: Options page not found.' ) );
 	}
 
 	if ( 'options' == $option_page ) {
Index: src/wp-includes/comment.php
===================================================================
--- src/wp-includes/comment.php	(revision 42413)
+++ src/wp-includes/comment.php	(working copy)
@@ -1186,19 +1186,19 @@
 	$max_lengths = wp_get_comment_fields_max_lengths();
 
 	if ( isset( $comment_data['comment_author'] ) && mb_strlen( $comment_data['comment_author'], '8bit' ) > $max_lengths['comment_author'] ) {
-		return new WP_Error( 'comment_author_column_length', __( '<strong>ERROR</strong>: your name is too long.' ), 200 );
+		return new WP_Error( 'comment_author_column_length', __( '<strong>ERROR</strong>: Your name is too long.' ), 200 );
 	}
 
 	if ( isset( $comment_data['comment_author_email'] ) && strlen( $comment_data['comment_author_email'] ) > $max_lengths['comment_author_email'] ) {
-		return new WP_Error( 'comment_author_email_column_length', __( '<strong>ERROR</strong>: your email address is too long.' ), 200 );
+		return new WP_Error( 'comment_author_email_column_length', __( '<strong>ERROR</strong>: Your email address is too long.' ), 200 );
 	}
 
 	if ( isset( $comment_data['comment_author_url'] ) && strlen( $comment_data['comment_author_url'] ) > $max_lengths['comment_author_url'] ) {
-		return new WP_Error( 'comment_author_url_column_length', __( '<strong>ERROR</strong>: your url is too long.' ), 200 );
+		return new WP_Error( 'comment_author_url_column_length', __( '<strong>ERROR</strong>: Your url is too long.' ), 200 );
 	}
 
 	if ( isset( $comment_data['comment_content'] ) && mb_strlen( $comment_data['comment_content'], '8bit' ) > $max_lengths['comment_content'] ) {
-		return new WP_Error( 'comment_content_column_length', __( '<strong>ERROR</strong>: your comment is too long.' ), 200 );
+		return new WP_Error( 'comment_content_column_length', __( '<strong>ERROR</strong>: Your comment is too long.' ), 200 );
 	}
 
 	return true;
@@ -3216,14 +3216,14 @@
 
 	if ( get_option( 'require_name_email' ) && ! $user->exists() ) {
 		if ( '' == $comment_author_email || '' == $comment_author ) {
-			return new WP_Error( 'require_name_email', __( '<strong>ERROR</strong>: please fill the required fields (name, email).' ), 200 );
+			return new WP_Error( 'require_name_email', __( '<strong>ERROR</strong>: Please fill the required fields (name, email).' ), 200 );
 		} elseif ( ! is_email( $comment_author_email ) ) {
-			return new WP_Error( 'require_valid_email', __( '<strong>ERROR</strong>: please enter a valid email address.' ), 200 );
+			return new WP_Error( 'require_valid_email', __( '<strong>ERROR</strong>: Please enter a valid email address.' ), 200 );
 		}
 	}
 
 	if ( '' == $comment_content ) {
-		return new WP_Error( 'require_valid_comment', __( '<strong>ERROR</strong>: please type a comment.' ), 200 );
+		return new WP_Error( 'require_valid_comment', __( '<strong>ERROR</strong>: Please type a comment.' ), 200 );
 	}
 
 	$commentdata = compact(
Index: src/wp-includes/ms-deprecated.php
===================================================================
--- src/wp-includes/ms-deprecated.php	(revision 42413)
+++ src/wp-includes/ms-deprecated.php	(working copy)
@@ -403,7 +403,7 @@
 	// Must restore table names at the end of function.
 
 	if ( ! $blog_id = insert_blog($domain, $path, $site_id) )
-		return __( '<strong>ERROR</strong>: problem creating site entry.' );
+		return __( '<strong>ERROR</strong>: Problem creating site entry.' );
 
 	switch_to_blog($blog_id);
 	install_blog($blog_id);