editor_command and file not modified message

I'm playing with a macro that with one key press follows up an
article with a predefined message.  Basically I thought of changing
the editor_command temporarily to a "cat file >> %s" type command,
call followup, and change editor back to vim.

Here's what I have:

#v+
define auto_message(){

  set_string_variable ("editor_command", "cat auto_message.txt >> '%s'");
  set_string_variable ("signature","");

  set_input_chars ("yy");
  set_prefix_argument(1);
  call ("followup");

  set_string_variable ("editor_command", "vim '+set ft=mail' '+set
tw=65' '+%d' '%s'");
  set_string_variable
("signature","/home/troy/.signature/usenet.signature");

}

definekey ("auto_message", "\e8", "article");
#v-

Trouble is that when I hit the key on a message, just the "file not
modified" error comes up and no followup is sent.  I've checked the
.followup and it is indeed getting the correct text inserted, so the
editor_command seems to be working.

Any ideas?

-- 
Troy Piggins                                         ,-O   (o-    O  
slrn macros and howto: http://piggo.com/~troy/slrn  O   )  //\     O
http://piggo.com/~troy                               `-O   V_/_  OOO
RLU#415538

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