make sure the config file is tagged as such

lmtp2nntp/lmtp2nntp.spec

@@ -84,7 +84,9 @@ AutoReqProv:  no
     %{l_shtool} install -c -m 644 \
         -e 's;@l_prefix@;%{l_prefix};g' \
         %{SOURCE lmtp2nntp.conf} $RPM_BUILD_ROOT%{l_prefix}/etc/lmtp2nntp.conf
-    %{l_rpmtool} files -v -ofiles -r$RPM_BUILD_ROOT %{l_files_std}
+    %{l_rpmtool} files -v -ofiles -r$RPM_BUILD_ROOT \
+        %{l_files_std} \
+        '%config %{l_prefix}/etc/lmtp2nntp/*'
 
 %files -f files