I am a Sr. Linux System Administrator for a very large hosting company and actually work monitoring servers. I deal with these bothersome bots on a daily basis (manually blocking them unfortunately), and it would be my pleasure to develop an extension for you. I have 7 years experience developing with PHP, and have created plugins for several popular cms platforms including Mediawiki. I can definitely handle this for you, but due to my work schedule I would need 3 to 5 days to ensure I deliver a tested and debugged product that performs exactly as expected.
Please let me know if you are interested by awarding the project, and sending a message my way.
Thank you for your time and consideration.