diff --git a/lisp/org-publish.el b/lisp/org-publish.el
index e78e2d4..cd77c82 100644
--- a/lisp/org-publish.el
+++ b/lisp/org-publish.el
@@ -1191,7 +1191,7 @@ Returns value on success, else nil."
 (defun org-publish-cache-ctime-of-src (f base-dir)
   "Get the FILENAME ctime as an integer."
   (let ((attr (file-attributes
-	       (expand-file-name (or (file-symlink-p f) f) base-dir))))
+	       (expand-file-name (or (file-symlink-p f) f) (file-name-directory f)))))
     (+ (lsh (car (nth 5 attr)) 16)
        (cadr (nth 5 attr)))))