I believe that XmlRpc++ is still a great library even though it has not been updated so long. It is light weighted and does not have any dependencies with other libraries. I found it has been very useful in interoperating with Python xmlrpc. The other day, I had added the Apache extension to support additional data types. It is highly compatible with the Python version. I would like to apply this extension to XmlRpc++. However, I am not sure if this SourceForge project is still under maintenance....