When unknown roster version, return an acceptable version ID binary (#2709)

diff --git a/src/mod_roster.erl b/src/mod_roster.erl
index 1f42b69e0e1c23af9b1bdb0454e40cc67f52a472..6d0b37bc3fb29ac267f4f8c4aef534352552685e 100644 (file)
--- a/src/mod_roster.erl
+++ b/src/mod_roster.erl
@@ -231,7 +231,7 @@ roster_version(LServer, LUser) ->
     case roster_version_on_db(LServer) of
       true ->
          case read_roster_version(LUser, LServer) of
-           error -> not_found;
+           error -> <<"not_found">>;
            {ok, V} -> V
          end;
       false ->