JMAP EmailSubmission/set rejects valid recipients whose domain is a bare public suffix (e.g. @gov.in, @nic.in)

Issue Description

EmailSubmission/set fails with invalidProperties on envelope for recipient addresses that are RFC-valid and deliverable, when the address’s domain is itself a registered public suffix (eTLD) on the Public Suffix List. Example: [email protected]. gov.in, nic.in, mil.in, ac.in, co.in etc. are all listed as public suffixes, yet NIC operates real mailboxes directly at those domains.

Expected Behavior

Submission accepted and queued for delivery (the address is RFC 5321-valid and the domain has valid MX).

Actual Behavior

{
“notCreated”: {
“s1”: {
“type”: “invalidProperties”,
“description”: “Invalid e-mail address “[email protected]”.”,
“properties”: [“envelope”]
}
}
}

Relevant Log Output

  1. Create a draft via Email/set with To: [email protected] — succeeds.
  2. Submit it via EmailSubmission/set — fails.

Stalwart Version

v0.16.x

Installation Method

Docker

Database Backend

MySQL

Blob Storage

S3-compatible

Search Engine

Internal

Directory Backend

Internal

I have reviewed the documentation and FAQ and confirm that my issue is NOT addressed there.

on

I have searched this support forum (open and closed topics) and confirm this is not a duplicate.

on

I understand that topics in this category are triaged by a bot first but a human reply will follow up. If I’d prefer a human-only reply, I’ll add the no-ai tag to my topic.

on

Fixed in v0.16.15 (yet to be released).