http://www.vmware.com/support/developer/vc-sdk/WS_FAQs.html
How do I check that the VirtualCenter Web service is installed properly?
Using a Web browser, open the document "Documents And Settings\All Users\Application Data\VMware\VMware VirtualCenter\VMA\login\login.html." Fill in the three fields: user name, password, and the full Web service URL; for example, https://localhost:8443. If an XML document appears in your browser, the Web service is running and responding to queries.
Can I use a non-SSL port with the VirtualCenter Web service?
Yes. For example, if you want to use the non-SSL port 8080, add the following entry to the vmaConfig.xml file, located in C:/Documents And Settings/All Users/Application Data/VMware/VMware VirtualCenter/VMA. Open vmaConfig.xml and look for the
Restart the Web service for any changes to vmaConfig.xml to take effect.
Can I install the Web service on a different box than the rest of VirtualCenter?
The VirtualCenter server and the VirtualCenter Web service should reside on the same machine. This is the only supported configuration.
How can I access the WSDL file programatically?
Access the vma.wsdl file by placing ?wsdl after the Web service URL; for example, https://localhost:8443?wsdl.