diff --git a/sql/structure.sql b/sql/structure.sql
index e4ee3609df797c91848f215e3a3dab791392f543..0b538f4c8d0f8a6558b68a750f24c74afdf61dcc 100755
--- a/sql/structure.sql
+++ b/sql/structure.sql
@@ -2652,7 +2652,7 @@ CREATE TABLE message_exchange
   
   res_id_master numeric default NULL,
 
-  docserver_id character varying(32) NOT NULL,
+  docserver_id character varying(32) DEFAULT NULL,
   path character varying(255) DEFAULT NULL,
   filename character varying(255) DEFAULT NULL,
   fingerprint character varying(255) DEFAULT NULL,