Has anyone else been able to use System.Net.Mail with GoDaddy?

I keep getting the following error: BC30002: Type 'NetworkCredential' is not defined.

I copied the code directly from a sample found on a System.Net.Mail site.  The sample also matches what I've seen on many other sites; so I'm sure the code is good.

I didn't put Imports System.Net.Mail at the top of my page, but placed <%@ Import Namespace="System.Net.Mail" %> the same way I import every other namespace.  Could this be causing the problem?

 
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