Recently, I get a news that about 40 website got SQL injection attack. These sites are attach by Encoded SQL script through a bot.
Here are some techincal information about the same
http://blogs.zdnet.com/security/?p=1059
http://www.gutizz.com/encoded-sql-injection/
Please make sure you have validate your Inputs to website, to avoid these attacks. These attacks refers to coding error/mistakes only and it is not MS SQL SERVER's error. So don't blame MS but your coder.
Have fun