I tried to upgrade to latest coppermine which offers a huge number of new features but the results were not good. I was not able to login to the new upgraded version. Worse, I didnt have any backup of the old database or files. I uploaded the files of one of the older version available on internet and I am able to use my album again though the index page shows some errors. But I am still attracted towards the newere version of Coppermine and hence I would be going for a fresh install. Lets see what happens 
At last it succeeded. I did a fresh install, and via MySQL tables, copied all data manually to the new album and it all works now