configuring IIS remotely

I am adding SMTP aliases using   C# programs with the following command.

DirectoryEntry entry = new DirectoryEntry("IIS://LOCALHOST/SMTPSVC/1");   

When I run it from the server where IIS is running everything works fine.  However when I run

it from a workstation with the proper IP address insstead of localhost, I get permission denied error.

 So the question is  is IIS protocol can be run this way? What kind of permissions needed? Kindly shed some light.

thanks