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--- a/src/internfile/mh_mail.h
+++ b/src/internfile/mh_mail.h
@@ -40,7 +40,7 @@
  */
 class MimeHandlerMail : public RecollFilter {
 public:
-    MimeHandlerMail(const string &mt);
+    MimeHandlerMail(RclConfig *cnf, const string &mt);
     virtual ~MimeHandlerMail();
     virtual bool set_document_file(const string& file_path);
     virtual bool set_document_string(const string& data);