If you are running on an old version of asterisk @ home then this is how you update asterisk to the latest version and also zaptel
#Asterisk Update
cd /usr/src/
rm -rf asterisk
wget http://ftp.digium.com/pub/asterisk/asterisk-1.2.18.tar.gz
tar zxfv asterisk-1.2.18.tar.gz
mv asterisk-1.2.18 asterisk
#Zaptel Update
cd /usr/src
rm -rf zaptel
wget http://ftp.digium.com/pub/zaptel/zaptel-1.2.17.1.tar.gz
tar -zxvf zaptel-1.2.17.1.tar.gz
mv zaptel-1.2.17.1 zaptel
#addons
cd /usr/src
rm -rf asterisk-addons
wget http://ftp.digium.com/pub/asterisk/asterisk-addons-1.2.6.tar.gz
tar -zxvf asterisk-addons-1.2.6.tar.gz
mv asterisk-addons-1.2.6 asterisk-addons
#libpri
cd /usr/src
rm -rf libpri
wget http://ftp.digium.com/pub/libpri/libpri-1.2.4.tar.gz
tar -zxvf libpri-1.2.4.tar.gz
mv libpri-1.2.4 libpri
./rebuildastsrc.sh
reboot
