Why does my Silverlight site and web service work everywhere but the production server (error included)?

My silverlight site/web service works fine in both a development and full test environment that mimics production; however, I get the following error when I go to the first page and attempt to make a web service call.  Any thoughts?
Oh yeah, running on IE 8 on all environments.

Webpage error details

User Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.0; WOW64; Trident/4.0; SLCC1; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET4.0C; .NET4.0E; .NET CLR 3.0.30729; MS-RTC LM 8)
Timestamp: Mon, 8 Nov 2010 17:06:36 UTC

Message: Unhandled Error in Silverlight Application [Async_ExceptionOccurred]
Arguments:
Debugging resource strings are unavailable. Often the key and arguments provide sufficient information to diagnose the problem. See http://go.microsoft.com/fwlink/?linkid=106663&Version=4.0.50917.0&File=System.dll&Key=Async_ExceptionOccurred   at System.ComponentModel.AsyncCompletedEventArgs.RaiseExceptionIfNecessary()
   at TransactionRetrieval.TransactionRetrievalServiceReference.isInDebugModeCompletedEventArgs.get_Result()
   at TransactionRetrieval.LoginControl.AfterIsInDebugMode(Object sender, isInDebugModeCompletedEventArgs e)
   at TransactionRetrieval.TransactionRetrievalServiceReference.TransactionRetrievalServiceClient.OnisInDebugModeCompleted(Object state)
Line: 1
Char: 1
Code: 0
URI: http://localhost/TransactionRetrieval2/Silverlight.js