I wished I would have read Rajeev's reply before...I just got it to work and reading all these replies...
What Rajeev said worked !! But not by setting it in tnsnames.ora file, but I had to do that using Oracle Net8 configuration assistant.
I changed orcl81.world to orcl81

One more thing , after I changed orcl81.world to orcl81
using oracle net8 configuration assistant, I did not find that change in any of the tnsnames.ora file. It works now. But where did my change got written ???

Whats the difference between using orcl81 and orcl81.world ??
All oracle examples show .world ...
Belive me I had tried everthing that SAM had mentioned... nothing was working !!
Thats why I use this forum and like it #@%

Thanks again
Sonali