The mailing list for listmasters using Sympa

[address@concealed]

I have some problems with header and footer.
If possible i would like to insert not text pure but complex code (html or 
similar), like header and footer in the messages sent by the users.
The problem is also that i would like to use the setting that allow each 
member to create a personal list (Allowing Creating list for all -).
Is it possible to insert a logo or an html code like header or footer, in 
automatic, in the messages of the lists created by the users (using the 
setting "Allowing Creating list for all").
At the moment i have failed.
I have only pure text in the header and footer. And i need to insert manually 
the files header.mime and footer.mime in each list created by the users (with 
"Allowing Creating list for all").
cp message.header.mime 
/home/sympamailinglist/expl/EACH_LIST_CREATED_BY_THE_USERS/
cp message.footer.mime 
/home/sympamailinglist/expl/EACH_LIST_CREATED_BY_THE_USERS/
-----------
drwxrwxr--    2 sympamailinglist psacln       4096 Apr 28 20:57 archives
-rw-r-----    1 sympamailinglist psacln        542 Apr 28 20:51 config
-rw-r-----    1 sympamailinglist psacln          0 Apr 28 20:51 
include_admin_user.lock
-rw-r-----    1 sympamailinglist psacln          0 Apr 28 20:55 include.lock
-rw-r-----    1 sympamailinglist psacln         31 Apr 28 20:51 info
-rw-r--r--    1 sympamailinglist psacln          8 Apr 28 22:57 
message.footer.mime
-rw-r--r--    1 sympamailinglist psacln        196 Apr 29 05:17 
message.header.mime
-rw-r-----    1 sympamailinglist psacln          9 Apr 29 06:13 msg_count
drwxr-x---    2 sympamailinglist psacln       4096 Apr 28 20:51 shared
-rw-r-----    1 sympamailinglist psacln         34 Apr 29 15:17 stats
----------------
In the documentation i have found only this link :
http://sympa.org/doc/html/node16.html#SECTION0016110000000000000000
I have created manually 2 file : message.header.mime and message.footer.mime. 
And i have copied them in each list created by the user.
The problem is that 
1) I see only header and footer in pure text. 
2) I prefer that sympa copy theunique header and footer in the messages 
without any intervention of me. I hate to copy the same file in the directory 
created for the user mailing lists (with "Allowing Creating list for all").
................
sympa.conf
................
## Local part of sympa email adresse
## Effective address will be [EMAIL]@[HOST]
email   sympa
## Default lang (fr | us | es | de | it | cn | tw | fi | pl | cz | hu | ro | 
et)
lang    us
## Who is able to create lists
## This parameter is a scenario, check sympa documentation about scenarios if 
you want to define one
#create_list    public_listmaster
create_list     free_for_all
## Specify which rfc2369 mailing list headers to add
# was rfc2369_header_fields ARRAY(0x85000f4)
rfc2369_header_fields   help,subscribe,unsubscribe,post,owner,archive
## Specify header fields to be removed before message distribution
# was remove_headers ARRAY(0x85000a0)
remove_headers  
Return-Receipt-To,Precedence,X-Sequence,Disposition-Notification-To
.................
wwsympa.conf
.................
###\ Errors management ////###
###\ MTA related ////###
###\ Pluggin ////###
## Path to MhOnarc mail2html pluggin
## This is required for HTML mail archiving
mhonarc /usr/bin/mhonarc
###\ S/MIME pluggin ////###
###\ Database ////###
###\ Web interface ////###
## Is fast_cgi module for Apache (or Roxen) installed (0 | 1)
## This module provide much faster web interface
# was use_fast_cgi 1
use_fast_cgi    0
----------------------