We have been helping a company consume our WCF services from Cold Fusion. I was surprised when a relatively simple WCF service caused an exception in the Cold Fusion 9 cfinvoke tag. The error message stated that there was an undefined portType in WSDL.
To solve the issue, declare a namespace in the ServiceBehavior attribute of your WCF service and leave the namespace empty in the ServiceContract attribute:
[ServiceContract]
[ServiceBehavior(Namespace = "http://yourdomainname.com/")]
Happy coding!