Email account hacked?

[Lalit Khajuria]

I got very weird msg today to my box:
- These recipients of your message have been processed by the mail server:
ari-matti.hedman@pp.inet.fi; Failed; 5.3.0 (other or undefined mail system
status)

Remote MTA 10.16.13.53: network error


- SMTP protocol diagnostic: 554 Message rejected by filter



So basicly this says I have spammed this guy, but I dont know who is and never even seen that email address.

I have changed my mailbox password on regular basis, and it 's over 10 letters long + some numbers.

As well I have ran virus-scans on regular basis.

So what the hell should I do now?

[FouTight]

nothing, more then likely someone else is sending it and it's being spoofed as your email address, so it only looks like it's comming from you.