Has anybody tried the Facebook Java library?

I have it in a project in Eclipse using Maven. I get this error when
trying to build the project.

C:\development\projects\workspace-3.2\foo\src\main\java\com\facebook
\api\FacebookRestClient.java:[811,50] incompatible types
found   : org.json.JSONStringer
required: org.json.JSONWriter

this is the line in question:
JSONWriter tagsJSON = new JSONStringer().array();

This doesn't seem to be a problem for anyone else as I have done
multiple searches for this problem and found nothing relevant.

I'm on WinXP using Eclipse 3.2.2, Java compiler is set to 5.0, maven
version is 2.0.6

thank you.