diff --git a/src/tests/bugs/doit.lsp b/src/tests/bugs/doit.lsp
index 797870750..641937092 100644
--- a/src/tests/bugs/doit.lsp
+++ b/src/tests/bugs/doit.lsp
@@ -37,6 +37,8 @@
 
 (load "cl-001.lsp")
 
+(load "mixed.lsp")
+
 (load "int-001.lsp")
 
 #-ecl-bytecmp
diff --git a/src/tests/bugs/mixed.lsp b/src/tests/bugs/mixed.lsp
new file mode 100644
index 000000000..8db62b4c6
--- /dev/null
+++ b/src/tests/bugs/mixed.lsp
@@ -0,0 +1,19 @@
+;-*- Mode:     Lisp -*-
+;;;; Contains: Some regression tests for ECL
+
+(in-package :cl-test)
+
+
+;;; (EXT:PACKAGE-LOCK) returned the wrong value.
+;;; Fixed in 77a267c7e42860affac8eddfcddb8e81fccd44e5
+
+(deftest mixed-0001-package-lock
+  (progn
+    ;; Don't know the first state
+    (ext:package-lock "CL-USER" nil)
+    (assert (eq nil
+                (ext:package-lock "CL-USER" t)))
+    (assert (eq t
+                (ext:package-lock "CL-USER" nil)))
+    (assert (eq nil
+                (ext:package-lock "CL-USER" nil)))))