Strange messages in mail queue

[Eric]

Chuck Swiger wrote:
> User Gandalf wrote:
>> Hello,
>>
>> I might be offtopic...
>> I always get a long daily output from periodic.
>>
>>
>> Mail in local queue:
>> -Queue ID- --Size-- ----Arrival Time---- -Sender/Recipient-------
>> 1D3C91DD4AA    45937 Tue May 23 10:54:42  MAILER-DAEMON
>>            (connect to onmail02.ongov.net[12.33.98.207]: Operation
>> timed out)
>>                                         robinrandall at ongov.net
>> 571EC1DD443    28752 Thu May 25 00:40:30  MAILER-DAEMON
>>                 (connect to paramed.biz[204.251.15.174]: Operation
>> timed out)
>>                                         nicholas at paramed.biz
>> C04121DD4A0    28736 Mon May 22 13:20:50  MAILER-DAEMON
>>            (connect to pistonheads.biz[195.225.218.139]: Operation
>> timed out)
>>                                         philip at pistonheads.biz
>>
>> and many others. Is this a breakin attempt? Or is this normal? I do
>> not know any of the e-mail addresses.
>> Thanks,
> 
> It's undelivered SPAM which your mail server is trying to bounce back to
> the sending machine.  In low quantities, it's annoying but harmless.  In
> higher volumes, it can put a drag on or even DoS your SMTP box.  Some
> combination of SpamAssassin, virus-scanning, Amavisd, or even
> greylisting will help....
> 

what MTA are you using?  i'm wondering why your server accepted the
email in the first place.