Consuming ASP.NET Web Service Problem

[Guest_imported]

I have a custom class in my web service one of my webmethods takes an array of this custom class as input. example:

Public Class someclass
   somepublic vars
End Class

<WebMethod()> Public Function somefunction(someinput() as someclass)
     somestuff
     return someoutput
End Function

I've build a proxy class for this and can successfully create an instance of my web service. However when I try to pass an array of someclass to the web service I get an error, details below.

response.write(myService.somefunction(someinput())

error:
[SoapException: System.Web.Services.Protocols.SoapException: Server was unable to process request. ---> System.IndexOutOfRangeException: Index was outside the bounds of the array.
at myService.somefunction(someclass[] someinput)
--- End of inner exception stack trace ---]