HttpContext.Current.Request.UserHostAddress Differences in ASP.NET 2.0 and 3.5

I get the following differences determining a localhost server.ASP.NET 2.0HttpContext.Current.Request.UserHostAddress = "127.0.0.1"
ASP.NET 3.5HttpContext.Current.Request.UserHostAddress = "::1"Is there a reason for this?? Thanks!
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