Comment

src/freedombone-adduser

 	SIP_EXTENSION=$(freedombone-sipfreeext)
     freedombone-addsipuser -u $MY_USERNAME -e $SIP_EXTENSION -p "$NEW_USER_PASSWORD"
     if [ ! "$?" = "0" ]; then
-        echo 'SIP user could not be added'
+        echo 'SIP user could not be added. Ensure that extension numbers are in order and do no exceed 299'
         userdel -r $MY_USERNAME
         exit 10
     fi