Adding another wsdl to the existing project

Hi I tried adding another wsdl (which is also a project) to existing project. And I am getting this error "WSDLException (at /con:soapui-project): faultCode=INVALID_WSDL: Expected element '{http://schemas.xmlsoap.org/wsdl/}definitions'."
I already made test cases to this project B & now I need to add this to project A that has many wsdl's in it. I tried right clicking & adding wsdl, then browsed to the saved project B & selecting it & I got the error above. can someone help me with this.

Thanks in advance.