http://plugins.jquery.com/project/jqSOAPClient

This is a jQuery implementation of SOAP Client and it is based on another jQuery plug-in called xmlObjectifier.

This is a jQuery implementation of SOAP Client and it is based on another jQuery plug-in called xmlObjectifier.
This library provides an easy way to communicate with SOAP web services from the client-side javascript (all domain restrictions are still there). SOAPClient supports complex/nested request objects as well as attributes and values within request object nodes. You can also set Header objects as well.
Practical example of how to use SOAPClient can be found on my site by following Demo link. I also have included a simple ASP.NET Proxy example that will resolve Cross-Browser Restrictions (if you're running IIS w/ ASP.NET)