Hi Jagdeesh & Zenobia,
Read your query..even am not much aware in detail about this topic & nor am a expert in this subject to guide you both..as half baked knowldge/opinion can be disastrous!!
What we would do is share the discussions on this topic which had happened on HR yahoogroups sometime back which i have stored..reading of the comments expressed may throw some light on this topic..
Hope this helps...
Cheers,
Rajat