ERROR: Could not retrieve a valid windows identity

When I try to create PowerView reports from BISM connection file, I get error:

<MoreInformation>
<Source>Microsoft.ReportingServices.ProcessingCore</Source>
<Message msrs:ErrorCode="rsErrorOpeningConnection" msrs:HelpLink="http://go.microsoft.com/fwlink/?LinkId=20476&amp;EvtSrc=Microsoft.ReportingServices.Diagnostics.Utilities.ErrorStrings&amp;EvtID=rsErrorOpeningConnection&amp;ProdName=Microsoft%20SQL%20Server%20Reporting%20Services&amp;ProdVer=11.0.3000.0" xmlns:msrs="http://www.microsoft.com/sql/reportingservices">Cannot create a connection to data source 'TemporaryDataSource'.</Message>
<MoreInformation>
<Source>Microsoft.AnalysisServices.AdomdClient</Source>
<Message/>
<MoreInformation>
<Source>Microsoft.SharePoint</Source>
<Message>Could not retrieve a valid Windows identity.</Message>
<MoreInformation>
<Source>mscorlib</Source>
<Message>WTS0003: The caller is not authorized to access the service.</Message>
</MoreInformation>
</MoreInformation>
</MoreInformation>
</MoreInformation>

From SharePoint logs: I get following exception details:

01/02/2013 11:00:34.17            w3wp.exe (0x0828)        0x2AEC SharePoint Foundation  Claims Authentication                bz7l        Medium              SPSecurityContext: Could not retrieve a valid windows identity for username 'DOMAIN\user' with UPN 'user@domain'. UPN is required when Kerberos constrained delegation is used. Exception: System.ServiceModel.EndpointNotFoundException: The message could not be dispatched because the service at the endpoint address 'net.pipe://localhost/s4u/022694f3-9fbd-422b-b4b2-312e25dae2a2' is unavailable for the protocol of the address.    Server stack trace:      at System.ServiceModel.Channels.ConnectionUpgradeHelper.DecodeFramingFault(ClientFramingDecoder decoder, IConnection connection, Uri via, String contentType, TimeoutHelper& timeoutHelper)     at System.ServiceModel.Channels.ClientFramingDuplexSessionChannel.SendPreamble(IConnection connection, ArraySegment`1 preamble, TimeoutHelper& timeoutHelper)     at System.ServiceModel.Channels.ClientFramingDuplexSessionChannel.DuplexConnectionPoolHelper.AcceptPooledConnection(IConnection connection, TimeoutHelper& timeoutHelper)     at System.ServiceModel.Channels.ConnectionPoolHelper.EstablishConnection(TimeSpan timeout)     at System.ServiceModel.Channels.ClientFramingDuplexSessionChannel.OnOpen(TimeSpan timeout)     at System.ServiceModel.Channels.CommunicationObject.Open(TimeSpan timeout)     at System.ServiceModel.Channels.ServiceChannel.OnOpen(TimeSpan timeout)     at System.ServiceModel.Channels.CommunicationObject.Open(TimeSpan timeout)     at System.ServiceModel.Channels.ServiceChannel.CallOnceManager.CallOnce(TimeSpan timeout, CallOnceManager cascade)     at System.ServiceModel.Channels.ServiceChannel.EnsureOpened(TimeSpan timeout)     at System.ServiceModel.Channels.ServiceChannel.Call(String action, Boolean oneway, ProxyOperationRuntime operation, Object[] ins, Object[] outs, TimeSpan timeout)     at System.ServiceModel.Channels.ServiceChannelProxy.InvokeService(IMethodCallMessage methodCall, ProxyOperationRuntime operation)     at System.ServiceModel.Channels.ServiceChannelProxy.Invoke(IMessage message)    Exception rethrown at [0]:      at System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg, IMessage retMsg)     at System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgData, Int32 type)     at Microsoft.IdentityModel.WindowsTokenService.S4UClient.IS4UService_dup.UpnLogon(String upn, Int32 pid)     at Microsoft.IdentityModel.WindowsTokenService.S4UClient.CallService(Func`2 contractOperation)     at Microsoft.SharePoint.SPSecurityContext.GetWindowsIdentity().                a1bef09b-025a-208e-cd5e-4ef6678b6d0d

Any help on how to get this resolved would be greatly appreciated.