Optus tole me through an email:
Dear Optus Internet Customer
We have been notified on 2011-03-01 by the Australian Communications and Media Authority (ACMA www.acma.gov.au) that your computer may be compromised by malware (such as a virus/trojan).
Optus Internet is a participant in the Australian Internet Security Initiative, run by the ACMA. The Initiative is aimed at identifying compromised computers (sometimes called "zombies") on the Australian Internet.
Computers can become compromised through the surreptitious installation of malicious software (malware) that enables the computer to be controlled remotely for illegal and harmful activities without the computer user's knowledge
Zombies are computers that have been infected by a computer virus or a similar intrusion, including hacking. Once infected, zombies can be used to commit online crimes remotely from anywhere in the world without the computer owner knowing. Online crimes include sending spam or hosting offensive material. Owners of the computers may also find themselves paying for bandwidth they did not know they were using.
Under the Initiative, Optus Internet receives daily lists of internet connections that are suspected of being linked to compromised computers. Your internet connection has appeared on this list.
The malware identified as the compromise on your computer is "Trojan: Mebroot".
Please take action to resolve this issue as soon as possible. We remind you that the terms of your contract require you to ensure that your use of the service does not affect other users or contravene any laws. Failure to take action to resolve this issue may lead to y our Optus Internet service being temporarily quarantined or suspended in order to protect the Optus Network and other internet users. (For more information, see the Optus Internet Acceptable Use Policy (Appendix H) at http://www.optus.com.au/standardagreements.
What you should do
The best way to prevent your computer being infected is to use anti-virus software and a firewall, and keep security patches up-to-date. You may also wish to consider anti-spyware software with a spam filter.
If you are already using anti-virus software, we recommend you update your virus scanning software then scan your system to detect & remove any virus you may have.
If you do not have a virus scanner there are many companies which offer software that can be downloaded or trialled from the Internet. More information about viruses and virus protection can be found at our Online Safety area at:
or at our online FAQ at:
If you have the Optus Internet Security Suite and need help with your subscription number or you Security Suite account, please go to the website
If you are having problems using the product, try the Help section within the application, which can be accessed via the Help button at the bottom left hand side of the Security Suite control panel.
If you have any queries regarding this email, please contact the Optus Internet Abuse Team on email@example.com.
Optus Internet Abuse Team