diff --git a/lib/private/comments/comment.php b/lib/private/comments/comment.php
index 36189d9523..27e63c9855 100644
--- a/lib/private/comments/comment.php
+++ b/lib/private/comments/comment.php
@@ -22,6 +22,7 @@ namespace OC\Comments;
 
 use OCP\Comments\IComment;
 use OCP\Comments\IllegalIDChangeException;
+use OCP\Comments\MessageTooLongException;
 
 class Comment implements IComment {
 
@@ -184,13 +185,18 @@ class Comment implements IComment {
 	 *
 	 * @param string $message
 	 * @return IComment
+	 * @throws MessageTooLongException
 	 * @since 9.0.0
 	 */
 	public function setMessage($message) {
 		if(!is_string($message)) {
 			throw new \InvalidArgumentException('String expected.');
 		}
-		$this->data['message'] = trim($message);
+		$message = trim($message);
+		if(mb_strlen($message, 'UTF-8') > IComment::MAX_MESSAGE_LENGTH) {
+			throw new MessageTooLongException('Comment message must not exceed ' . IComment::MAX_MESSAGE_LENGTH . ' characters');
+		}
+		$this->data['message'] = $message;
 		return $this;
 	}
 
diff --git a/lib/public/comments/icomment.php b/lib/public/comments/icomment.php
index e695b5193f..a7f4b4c617 100644
--- a/lib/public/comments/icomment.php
+++ b/lib/public/comments/icomment.php
@@ -29,6 +29,7 @@ namespace OCP\Comments;
  * @since 9.0.0
  */
 interface IComment {
+	const MAX_MESSAGE_LENGTH = 1000;
 
 	/**
 	 * returns the ID of the comment
@@ -119,8 +120,12 @@ interface IComment {
 	/**
 	 * sets the message of the comment and returns itself
 	 *
+	 * When the given message length exceeds MAX_MESSAGE_LENGTH an
+	 * MessageTooLongException shall be thrown.
+	 *
 	 * @param string $message
 	 * @return IComment
+	 * @throws MessageTooLongException
 	 * @since 9.0.0
 	 */
 	public function setMessage($message);
diff --git a/lib/public/comments/messagetoolongexception.php b/lib/public/comments/messagetoolongexception.php
new file mode 100644
index 0000000000..5b2809ae9c
--- /dev/null
+++ b/lib/public/comments/messagetoolongexception.php
@@ -0,0 +1,27 @@
+<?php
+/**
+ * @author Arthur Schiwon <blizzz@owncloud.com>
+ *
+ * @copyright Copyright (c) 2016, ownCloud, Inc.
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+namespace OCP\Comments;
+
+/**
+ * Exception for not found entity
+ * @since 9.0.0
+ */
+class MessageTooLongException extends \Exception {}
diff --git a/tests/lib/comments/comment.php b/tests/lib/comments/comment.php
index e6f9c941c9..9b3f2ab166 100644
--- a/tests/lib/comments/comment.php
+++ b/tests/lib/comments/comment.php
@@ -2,6 +2,7 @@
 
 namespace Test\Comments;
 
+use OCP\Comments\IComment;
 use Test\TestCase;
 
 class Test_Comments_Comment extends TestCase
@@ -107,6 +108,15 @@ class Test_Comments_Comment extends TestCase
 		$comment->$setter($type, $id);
 	}
 
+	/**
+	 * @expectedException \OCP\Comments\MessageTooLongException
+	 */
+	public function testSetUberlongMessage() {
+		$comment = new \OC\Comments\Comment();
+		$msg = str_pad('', IComment::MAX_MESSAGE_LENGTH + 1, 'x');
+		$comment->setMessage($msg);
+	}
+
 
 
 }