One of the internet users at our company is plagued with about 100 purely spam emails to his email address every day.  To help aleviate this, he has an email account at mailshell.com that automatically retrieves all his email to "his_account@mailshell.com".  Mailshell has several anti-spam tools that he has configured to "screen" his mail before it is downloaded to our intranet email server via fetchmail.  Here's the problem: we just changed our email hosting to lunarpages, and mailshell can no longer download his email from mail.ourdomain.com.  I suspect it has something to do with requiring the "@" as part of his username, but he has tried using +, :, and %, but still gets authentication errors.  I think mailshell is fairly popular and I'm hoping somebody has experienced (and resolved!) this problem before.

Any ideas on this would be appreciated...thanks in advance...
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