diff --git a/file/lib/system/attachment/MessageAttachmentObjectType.class.php b/file/lib/system/attachment/MessageAttachmentObjectType.class.php
new file mode 100644
index 0000000..a9553ec
--- /dev/null
+++ b/file/lib/system/attachment/MessageAttachmentObjectType.class.php
@@ -0,0 +1,65 @@
+<?php
+namespace chat\system\attachment;
+
+/**
+ * Attachment object type implementation for chat messages.
+ *
+ * @author 	Maximilian Mader
+ * @copyright	2010-2013 Tim Düsterhus
+ * @license	Creative Commons Attribution-NonCommercial-ShareAlike <http://creativecommons.org/licenses/by-nc-sa/3.0/legalcode>
+ * @package	be.bastelstu.chat
+ * @subpackage	system.attachment
+ */
+class MessageAttachmentObjectType extends AbstractAttachmentObjectType {
+	/**
+	 * @see	wcf\system\attachment\IAttachmentObjectType::getMaxSize()
+	 */
+	public function getMaxSize() {
+		return WCF::getSession()->getPermission('user.chat.maxAttachmentSize');
+	}
+	
+	/**
+	 * @see	wcf\system\attachment\IAttachmentObjectType::getAllowedExtensions()
+	 */
+	public function getAllowedExtensions() {
+		return ArrayUtil::trim(explode("\n", WCF::getSession()->getPermission('user.chat.allowedAttachmentExtensions')));
+	}
+	
+	/**
+	 * @see	wcf\system\attachment\IAttachmentObjectType::getMaxCount()
+	 */
+	public function getMaxCount() {
+		return 1;
+	}
+	
+	/**
+	 * @see	wcf\system\attachment\IAttachmentObjectType::canDownload()
+	 */
+	public function canDownload($objectID) {
+		if ($objectID) {
+			$room = \chat\data\room\RoomCache::getInstance()->getRoom($objectID);
+			if ($room && $room->canEnter()) return true;
+		}
+		
+		return false;
+	}
+	
+	/**
+	 * @see	wcf\system\attachment\IAttachmentObjectType::canUpload()
+	 */
+	public function canUpload($objectID, $parentObjectID = 0) {
+		if ($objectID) {
+			$room = \chat\data\room\RoomCache::getInstance()->getRoom($objectID);
+			if ($room && $room->canWrite()) return true;
+		}
+		
+		return WCF::getSession()->getPermission('user.chat.canUploadAttachment');
+	}
+	
+	/**
+	 * @see	wcf\system\attachment\IAttachmentObjectType::canDelete()
+	 */
+	public function canDelete($objectID) {
+		return false;
+	}
+}