http_request event

Hello everyone,
      I am trying to analyze http traffic using Bro, but I couldn't make
http_request event fire even I have loaded http analyzer (includes all
http*.bro files related to http) in mt.bro. I am able to see http traffic in
the new_connection event handler, but not in http_request event handler. What
am I missing for making http analyer work? thanks.

Bing