diff --git a/dev-libs/open62541/metadata.xml b/dev-libs/open62541/metadata.xml
index 9ef64b248a..0dafe429e2 100644
--- a/dev-libs/open62541/metadata.xml
+++ b/dev-libs/open62541/metadata.xml
@@ -5,7 +5,7 @@
     <email>kurt@kmk-computers.de</email>
     <name>Kurt Kanzenbach</name>
   </maintainer>
-  <longdescription>
+  <longdescription lang="en">
     open62541 (http://open62541.org) is an open source and free implementation
     of OPC UA (OPC Unified Architecture) written in the common subset of the C99
     and C++98 languages. The library is usable with all major compilers and