diff --git a/lisp/ob-tangle.el b/lisp/ob-tangle.el
index 14ef97b9a..a835915b7 100644
--- a/lisp/ob-tangle.el
+++ b/lisp/ob-tangle.el
@@ -354,6 +354,7 @@ form
        insert-comment
        (org-fill-template org-babel-tangle-comment-format-end link-data)))))
 
+(defvar org-comment-string) ;; Defined in org.el
 (defun org-babel-tangle-collect-blocks (&optional language)
   "Collect source blocks in the current Org-mode file.
 Return an association list of source-code block specifications of
diff --git a/lisp/org-mew.el b/lisp/org-mew.el
index cfe99284f..ab1b279d4 100644
--- a/lisp/org-mew.el
+++ b/lisp/org-mew.el
@@ -126,6 +126,7 @@ with \"t\" key."
 (declare-function mew-case-folder "ext:mew-func" (case folder))
 (declare-function mew-folder-path-to-folder
 		  "ext:mew-func" (path &optional has-proto))
+(declare-function mew-idstr-to-id-list "ext:mew-header" (idstr &optional rev))
 (declare-function mew-folder-remotep "ext:mew-func" (folder))
 (declare-function mew-folder-virtualp "ext:mew-func" (folder))
 (declare-function mew-header-get-value "ext:mew-header"