Error in Build Web Dynpro DC with KM APIs

Dear all,

Im trying to build a WebDynpro DC that uses KM APIs, but I got the following error like:

"package com.sapportals.wcm.repository does not exist"

I have read the blog Uploading files to KM repository using Webdynpro APIs ( /people/rohit.radhakrishnan/blog/2005/05/27/uploading-files-to-km-repository-using-webdynpro-apis ).

I have set the references in Developer Studio in Window >preferences>java>classpath variables and have extended the variables in Java build Path on my DC. I have noticed that once i make a build in my DC, the references desappear in Java build Path, and I get the error shown before.

Can somebody help me?

Thanks a lot!

Luiza