[ietf-dkim] Weird i= in client mail

Laura Atkins laura at wordtothewise.com
Mon Jun 17 14:36:38 PDT 2013

I am in the process of reviewing the technical setup of a client installation. This client is using the VERP string (Return Path / Envelope From) in the i= of their DKIM signature.

The signature looks like this:

DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; s=ci; d=inbox.example.com;
	i=verpprefix-laura=2dinterdirect=40wordtothewise.com-2979-83348823-24644-bounce at inbox.example.com;

Based on my understanding of DKIM, this isn't necessarily violating the DKIM spec, but it does seem to be not the right thing to use for the i= value

I'm thinking my client should stop doing this, just because it really seems wrong but I have no justification for recommending that other than "that can't be right." 

I haven't been able to find anything that discusses the intention behind the i=. I expect they chose this i= because that's the envelope from, but the i= is suppose to be a person, not a mechanical address, correct?

I'd appreciate any guidance on where to go to research this. Or if anyone can give me some help in understanding this enough to tell my client to stop. 


Laura Atkins
Word to the Wise			"The Deliverability Experts!"
Direct: 650 678-3454		Fax: 650 249-1909
AIM: wttwlaura			YIM: wttw_laura
Delivery blog: <http://blog.wordtothewise.com/>

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