Incoming mail from M365 shared mailbox with multiple SMTP addresses

[SVT]

Hi,

we are trying to use the incoming mail feature with Exchange Online. As basic auth will be abandoned soon by Microsoft, we connect using OAuth2.

Works quite well. We now have a serious issue with the mail processing. We use one user mailbox with multiple proxyAddresses defined:

User is jira_mbx-agent@blubb.com and for our project we added smtp aliases:

SMTP:jira-1@blubb.com

SMTP:jira-2@blubb.com

SMTP:jira-3@blubb.com

We now have defined 3 rules in jira cloud for incoming mail that use the same connection (via jira_mbx-agent@blubb.com) but scan for a different recipient address.

This does not work when the mail is sent by internal users. Even though the mails were i.e. sent to jira-1@blubb.com, the default smtp address is acknowledged by jira cloud not the real recipient address in the mail itself which is correctly set to "To:jira-1@blubb.com".

Is it possible for Jira to scan the "To:" field in the mail and not use the default mail address of the recipient mailbox?

I would like to prevent the need for multiple mailboxes as each box would need a license and the IMAP way to use one shared mailbox with rules in subfolders does not work to :/

Best regards,

Sven