diff --git a/src/um/User.cc b/src/um/User.cc
index 335ae9c0eb..0d7706ff61 100644
--- a/src/um/User.cc
+++ b/src/um/User.cc
@@ -53,7 +53,7 @@ const char * User::table = "user_pool";
 const char * User::db_names = "(oid,user_name,password,enabled)";
 
 const char * User::db_bootstrap = "CREATE TABLE user_pool ("
-    "oid INTEGER PRIMARY KEY, user_name TEXT, password TEXT,"
+    "oid INTEGER PRIMARY KEY, user_name VARCHAR(256), password TEXT,"
     "enabled INTEGER, UNIQUE(user_name))";
 
 /* -------------------------------------------------------------------------- */