Twisted-0.17.3 semms to have some Problems decoding CNAME records. It
has an off by two error which completely messes up the decoding
process.  The attached patch seems to cure the problem, but I'm not
sure why the author did this fiddeling with the offset.

Nevertheless this patch works for me - perhaps by coincidence.

  --drt@un.bewaff.net - http://c0re.jp/c0de/misc/

diff -ur Twisted-0.17.3-orig/twisted/names/dns.py Twisted-0.17.3/twisted/names/dns.py
--- Twisted-0.17.3-orig/twisted/names/dns.py	Tue Apr  9 22:37:00 2002
+++ Twisted-0.17.3/twisted/names/dns.py	Sat May  4 20:06:51 2002
@@ -156,7 +156,7 @@
             if answer.type == 1:
                 answers.append(answer)
             elif answer.type == dns.CNAME:
-                answer.strio.seek(answer.strioOff+2)
+                answer.strio.seek(answer.strioOff)
                 n = dns.Name()
                 n.decode(answer.strio)
                 cnames.append(n.name)
@@ -168,7 +168,7 @@
                 if answer.type == 1:
                     answers.append(cnameMap[name])
                 else:
-                    answer.strio.seek(answer.strioOff+2)
+                    answer.strio.seek(answer.strioOff)
                     n = dns.Name()
                     n.decode(answer.strio)
                     name = n.name