Mystery 'ne.jp' entry in Mail Shield SSL Accounts

Twice recently when looking at my Mail Shield SSL Accounts entries, I have noticed a mystery ‘ne.jp’ entry in there.

As my sole email provider is GMX (POP3 via Outlook Express), I have only ever previously seen ‘gmx.net’ entries in there.

What could be causing the mystery ‘ne.jp’ to appear all of a sudden and how might I stop it from re-appearing? I deleted it once a couple of weeks ago, but I noticed it reappeared today, so have deleted it again.