Okay folks, with all the help from you guys, I have this working pretty well now.

For the benefit of others designing an IR transmitter powered from a typical coin battery, I would like to share this point. Once you have the basic thing working, probably the one single factor to increase the range significantly would be a large capacitor (100uf plus) across the battery.

I dont know how this would impact the battery life though.

Regards,

Anand