The spammer has created new accounts with usernames like AdminModerator, BoardSupport, ModAdmin, AdminMod, AdminGirl, and other similar names.
Here is an example of the spam:


Warning! Next time we will have to complaint to your ISP.

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Dear, (your username)

A virus alert was noticed on your computer.
We highly recommend you to check your computer and perform online virus check at our site immediately: http://securitytool2010.com/
If you do not pass this test* we will have to delete your account and forward a complaint to your ISP with attached log file (your IP address, etc.).
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Forum Administration oldsmobileforum.com.


This is spam and does not come from Oldsmobile forum! Do not click on the link in the message!
As Rustyballs_69 said in the announcment above, report to him or myself so we can delete the accounts.
Iflylow