Thanks for the replies.

Finally, after calling Etihad call center for almost 10 times, one of the rep told that no Transit visa is required if we stay at the airport for 24hrs. This contradicts to the reply which Kshastry received. Also, I came across a link of Abu Dhabi airport which mentions about visa if stay is more than 4hrs:
http://www.abudhabiairport.ae/englis...n-4-hours.aspx
Now this link does not clearly mention that if we do not wish to leave the airport then is the visa really needed or not. Hence all the information is confusing. I wish they can put it very clearly for their passengers so no one gets into trouble.