Cannot get CDATA to work

I went thru a few posts in this list, but still no luck to get CATA to work.
I am using xmlbeans version 2.4.
What's wrong with the followings?

node.setKey("ABCDEFG");
XmlCursor c = node.xgetKey().newCursor();
c.toFirstContentToken();
c.setBookmark(CDataBookmark.CDATA_BOOKMARK);
System.out.println(node);