i got error while creating a android project in eclipse 3.6.1

I got the following error on error log,

"conversion to dalvik format failed with error 1"

How to resolve this issue?

Quote from http://d.android.com/sdk/eclipse-adt.html:

Caution: There are known issues with the ADT plugin running with Eclipse 3.6. Please stay on 3.5 until further notice.

I find that typically when I get this error, it can be easily resolved by cleaning the project and rebuilding (Project->Clean).