Has anyone had any luck with getting Courier (2.5.4.1) to publish to a site where the destination is protected by HTTPAUTH?  Is that supported?  Any tips to getting it to work?

I'm attempting to publish to some third-party hosting where it's not possible to change the IIS configuration, but get the following error when I select the destination under "Locations" on my source/dev machine.

The request failed with HTTP status 404: Not Found.
Error details


System.Net.WebException: The request failed with HTTP status 404: Not Found. 
at System.Web.Services.Protocols.SoapHttpClientProtocol.ReadResponse(SoapClientMessage message, WebResponse response, Stream responseStream, Boolean asyncCall) 
at System.Web.Services.Protocols.SoapHttpClientProtocol.Invoke(String methodName, Object[] parameters) 
at Umbraco.Courier.RepositoryProviders.WebServiceProvider.RepositoryWebservice.GetAvailableRevisions(String username, String password) in c:\Program Files (x86)\teamcity\buildAgent\work\d94035a1177dda67\Umbraco.Courier.RepositoryProviders\WebserviceProvider\webservice.cs:line 700 
at Umbraco.Courier.RepositoryProviders.CourierWebserviceRepositoryProvider.GetAvailableRevisions() in c:\Program Files (x86)\teamcity\buildAgent\work\d94035a1177dda67\Umbraco.Courier.RepositoryProviders\WebserviceProvider\CourierWebserviceRepositoryProvider.cs:line 106 
at Umbraco.Courier.Core.RepositoryProvider.GetAvailableRevisions(String folder) 
at Umbraco.Courier.UI.Pages.editRepository.OnInit(EventArgs e) 
at System.Web.UI.Control.InitRecursive(Control namingContainer) 
at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)

(Note that publishing to sites without auth does work just fine)

Any help much appreciated :)