Getting XmlRpcException when I try to add a custom taxonomy to the post

[mdaddy]

Hello,
When I try to add a custom taxonomy, I get the following error:

Exception in thread "main" redstone.xmlrpc.XmlRpcException: The response could not be parsed.

It works fine when I add a category or a tag.
The line where it gives error is:
final List<Term> terms = wp.getTerms("author");

My custom taxonomy is author. If I swap "author" with "category" or "post_tag", the code goes through and it adds the category or tag with the post. But when I try to use the same code for a custom taxonomy, I get the error.

Is there another way to use custom taxonomy?
thanks,

[canbican]

Do you have the custom taxonomy already defined in the installation?