使用wsdl工具时，对象引用未设置为对象的实例

Question

我正试图从这个wsdl获得课程

http://e-pelmex.com.br/services/soap?wsdl

但是我得到了这个错误

nati pelmex # wsdl  http://e-pelmex.com.br/services/soap?wsdl
    Web Services Description Language Utility
    Mono Framework v4.0.30319.17020
    Error: Object reference not set to an instance of an object
    Stack:
       at System.Xml.Serialization.XmlSerializationReader.OnUnknownNode (System.Xml.XmlNode node, System.Object o, System.String qnames) [0x00000] in <filename unknown>:0 
      at System.Xml.Serialization.XmlSerializationReader.UnknownNode (System.Object o, System.String qnames) [0x00000] in <filename unknown>:0 
      at System.Xml.Serialization.XmlSerializationReader.UnknownNode (System.Object o) [0x00000] in <filename unknown>:0 
      at System.Web.Services.Description.ServiceDescriptionReaderBase.ReadObject_ServiceDescription (Boolean isNullable, Boolean checkType) [0x00000] in <filename unknown>:0 
      at System.Web.Services.Description.ServiceDescriptionReaderBase.ReadRoot_ServiceDescription () [0x00000] in <filename unknown>:0 
      at System.Web.Services.Description.ServiceDescription+ServiceDescriptionSerializer.Deserialize (System.Xml.Serialization.XmlSerializationReader reader) [0x00000] in <filename unknown>:0 
      at System.Xml.Serialization.XmlSerializer.Deserialize (System.Xml.XmlReader xmlReader) [0x00000] in <filename unknown>:0 
      at System.Web.Services.Description.ServiceDescription.Read (System.Xml.XmlReader reader) [0x00000] in <filename unknown>:0 
      at System.Web.Services.Discovery.DiscoveryClientProtocol.DiscoverAny (System.String url) [0x00000] in <filename unknown>:0 
      at (wrapper remoting-invoke-with-check) System.Web.Services.Discovery.DiscoveryClientProtocol:DiscoverAny (string)
      at Mono.WebServices.Driver.Run (System.String[] args) [0x00000] in <filename unknown>:0 
    nati pelmex #

有什么想法吗？