Well, as I had kind of thought early on with this issue, I think it was caused by the generated POJO classes from the WSDL not having the XmlRootElement annotation. I found the way to force this during wsdl2java (putting <xjc:simple /> in the bindings.xml file). Once I did that, convertBodyTo started working!! Sorry for the unnecessary post. Hopefully someone else having this issue will find my resolution at some point in the future!