cd /usr/src
svn co http://svn.ohnosec.org/svn/projects/allstar/astsrc-1.4.23-pre/trunk/
this creates a
trunk directory.
Source code can be browsed
here
http://svn.ohnosec.org/svn/projects/allstar/astsrc-1.4.23-pre/trunk/fixed-dahdi-patches/
http://svn.ohnosec.org/svn/projects/allstar/astsrc-1.4.23-pre/trunk/
http://www.asterisk.org/downloads/dahdi
Create a /usr/src/asterisk and untar the acid svn there.
create /usr/src/utils/dahdi and untar dahdi there.
Also untar the dahdi patches and apply them. Readme shows how.
./configure
make
sudo make install