Get Host Name

I use this line of code to get the host name from a system:

 System.Net.IPHostEntry obj = new IPHostEntry();
obj = Dns.GetHostByName(Request.UserHostAddress);
String HostName = obj.HostName.ToString();

and this retrieves this Host Name: bea-som.corp.bea.org

 

However from my client application I call this:

 System.Net.Dns.GetHostName()

and this retrieves the host name as: bea-som

 

What changes do I make to either the C# client application or website so that both of them take the same host name ?
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