diff --git a/services/entropy-pkgdelta-generator b/services/entropy-pkgdelta-generator
index ff8faafd5..01d623f4d 100755
--- a/services/entropy-pkgdelta-generator
+++ b/services/entropy-pkgdelta-generator
@@ -224,7 +224,7 @@ if __name__ == "__main__":
         if lock_file:
             acquired = entropy.tools.acquire_lock(lock_file, lock_map)
             if not acquired:
-                sys.stderr.write("cannot acquire lock on " + lock_file + "\n")
+                sys.stdout.write("cannot acquire lock on " + lock_file + "\n")
                 raise SystemExit(5)
         try:
             rc = func(argv, quiet)