ExtJS Exception - Effect.Morph is not a construction

Hi,

I am using ExtJS in my application. I am getting the following
javascript error.

  "Effect.Morph is not a constructor"

The application was working well yesterday. But today I am getting this
error. I didn't change anything in the code. I don know why I am getting
this error.

Any suggestion is appreciated.

Thanks in advance.

- Karthik.