[dns-wg] DNSSEC breaks qmail

> Qmail can't deliver to DNSSEC protected domains. (Repost from 
edri.org-ML)
> 
> Reason:
>   - qmail send an "ANY IN edri.org" query in order to deliver mail.
>   * Due to DNSSEC, there are a some signatures catched by ANY so the
>     response packet size is 605 bytes.
>   - qmail does not support EDNS extensions for larger UDP packets.
>   * The response is truncated to 512 bytes and marked "truncated".
>   - qmail does not support the very old TCP fallback requirement for 
DNS.
>   - qmail refuses to deliver the mail
>     and logs "CNAME_lookup_failed_temporarily."

I can think of non-dnssec responses that are larger than 512 octets, so 
the subject of this message does not cover its content. I am not sure what 
CNAME has to do with this. I have seen patches for qmail that make it 
handle larger udp packet sizes. Which service marks a DNS message 
'truncated' in your example ? 

Roy