[grails + xfire] How to map geo types?

Question

Hi all, I have this class in Grails:

import com.vividsolutions.jts.geom.Point

class MouseMove {

    /** map latlon coordinates */
    Point geoLocation


    // other stuff

    static mapping = {
         geoLocation type: org.hibernatespatial.GeometryUserType
    }
}

When I try to return this class in an xfire service, the SOAP client gets this error:

Couldn't get property {http://geom.jts.vividsolutions.com} boundary 
from bean GEOMETRYCOLLECTION EMPTY. Nested exception is java.lang.reflect.InvocationTargetException:

Any idea on what I can do to map the new class on xfire?

Cheers!