SocketException on UI Service

I've experienced a few occassions where the UI service crashes and the page becomes inaccessible while the service restarts. I haven't captured all of the logs when this occurred, but below is the latest. Can you offer any guidance on this particular exception?


2012-10-23 16:12:49,020 [ 7] FATAL
RedGate.Response.UI.Website.MvcApplication - System.Net.Sockets.SocketException: An operation was attempted on something that is not a socket
at System.Net.Sockets.Socket.DoBeginAccept(Socket acceptSocket, Int32 receiveSize, AcceptOverlappedAsyncResult asyncResult)
at System.Net.Sockets.Socket.BeginAccept(Socket acceptSocket, Int32 receiveSize, AsyncCallback callback, Object state)
at System.Net.Sockets.Socket.BeginAccept(AsyncCallback callback, Object state)
at Mono.WebServer.ApplicationServer.OnAccept(IAsyncResult ares)
at System.Net.LazyAsyncResult.Complete(IntPtr userToken)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Net.ContextAwareResult.Complete(IntPtr userToken)
at System.Net.LazyAsyncResult.ProtectedInvokeCallback(Object result, IntPtr userToken)
at System.Net.Sockets.BaseOverlappedAsyncResult.CompletionPortCallback(UInt32 errorCode, UInt32 numBytes, NativeOverlapped* nativeOverlapped)
at System.Threading._IOCompletionCallback.PerformIOCompletionCallback(UInt32 errorCode, UInt32 numBytes, NativeOverlapped* pOVERLAP)