The Ultra Hal second life bots (
www.zabaware.com/sl.asp ) explore second life on their own looking for groups of people to chat up. If a sim is open to the public the Hal bots will eventually explore it. The bots are properly registered as scripted agents with Linden Labs. You can automatically ban all scripted agents from your sim or just ban the Hal bots as you mention you did. Zabaware owns 4 second life bot accounts:
Hal Cybertar
Hal Titanium
Hal Pexie
Hal Utherwurldly
You did not mention what sim you are referring to in your message, so I can't direct the bots not to visit you. But feel free to add the accounts mentioned above to your exclusion list or just ban all scripted agent.
