[asterisk-r2] Patched chan_dahdi.so refuses to be loaded

[David Matias Hernandez]

Hi all,
I'm currently trying to install an Asterisk 1.6.0.22 with OpenR2 - MFC signalling for an E1 link.
I have installed Dahdi-Linux, Dahdi-tools, libpri and openr2 libraries without any problem, always using --prefix=/usr as it's told in almost every forums/manuals.
Chan_dahdi.c has been manually patched (Hunk #19 fails) with openr2-asterisk-1.6.0.6 patch, it's attached on the email. It looks like there's no problem at compilation time.
But when asterisk starts, chan_dahdi.so refuses to load. Setting log => verbose on logger.conf, that's what I see when i try to load manually the module:

pbx*CLI> module load chan_dahdi.so
Unable to load module chan_dahdi.so
Command 'module load chan_dahdi.so ' failed.
[Feb 14 16:10:30] WARNING[11204]: loader.c:446 load_dynamic_module: Error loading module 'chan_dahdi.so': /usr/lib/asterisk/modules/chan_dahdi.so: undefined symbol: openr2_chan_disable_read
[Feb 14 16:10:30] WARNING[11204]: loader.c:770 load_resource: Module 'chan_dahdi.so' could not be loaded.

Also, chan_dahdi.so is not static linked to openr2 libraries:

 pbx:~# ldd /usr/lib/asterisk/modules/chan_dahdi.so
         linux-gate.so.1 =>  (0xb7f49000)
         libtonezone.so.2.0 => /usr/lib/libtonezone.so.2.0 (0xb7ea8000)
         libpri.so.1.4 => /usr/lib/libpri.so.1.4 (0xb7e7d000)
         libpthread.so.0 => /lib/i686/cmov/libpthread.so.0 (0xb7e63000)
         libc.so.6 => /lib/i686/cmov/libc.so.6 (0xb7d08000)
         libm.so.6 => /lib/i686/cmov/libm.so.6 (0xb7ce2000)
         /lib/ld-linux.so.2 (0xb7f4a000)

I'm using Debian Lenny 5.02, with these links to install asterisk stuff:

http://downloads.asterisk.org/pub/telephony/asterisk/releases/asterisk-1.6.0.22.tar.gz
http://downloads.asterisk.org/pub/telephony/dahdi-linux/releases/dahdi-linux-2.2.1.tar.gz
http://downloads.asterisk.org/pub/telephony/dahdi-tools/releases/dahdi-tools-2.2.1.tar.gz
http://downloads.asterisk.org/pub/telephony/libpri/releases/libpri-1.4.10.2.tar.gz
http://downloads.asterisk.org/pub/telephony/asterisk/releases/asterisk-addons-1.6.0.4.tar.gz

Any help to solve this problem would be kindly appreciated  :) 
Thanks in advance,

David