When someone mails to issue@(ourdomain), Jira will automatic make a issue for the mail that has been send to it. But there is 1 user and his mails are not being transferred to Jira. I can see his mail in the Issue@(ourdomain) inbox, but it won't sent it to Jira.
This problem is weird from my kind of view, since it should automatically send the mail from the mailbox to Jira. All incoming mails are being processed except his mails.