Vista - xps document can not show in IE

hi ,I have setup Feb. CTP, when I open the xps document in IE, error occurs
below
Any body has good ideas about it ??

Tks
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Startup URI:
D:\WinFXDemo\WindowsPresentationFoundation\DocServices\XpsSave\CSharp\Content\ViewOneVisual.xps
Application Identity:

System.Security.SecurityException: Request for the permission of type
'System.Security.Permissions.SecurityPermission, mscorlib, Version=2.0.0.0,
Culture=neutral, PublicKeyToken=b77a5c561934e089' failed.
at System.Xml.XmlException.GetObjectData(SerializationInfo info,
StreamingContext context)
at System.Runtime.Serialization.ObjectCloneHelper.GetObjectData(Object
serObj, String& typeName, String& assemName, String[]& fieldNames, Object[]&
fieldValues)



at MS.Internal.AppModel.ApplicationProxyInternal.Run()
at
System.Windows.Interop.DocObjHost.MS.Internal.AppModel.IBrowserHostServices.Run(String
path, String viewerUri, String fragment, String applicationId, MimeType mime,
Object streamContainer, Object ucomLoadIStream, Boolean isDebugMode, Boolean
isAvalonTopLevel, String progressAssemblyName, String progressClassName,
String errorAssemblyName, String errorClassName)
The action that failed was:
Demand
The type of the first permission that failed was:
System.Security.Permissions.SecurityPermission
The first permission that failed was:
<IPermission class="System.Security.Permissions.SecurityPermission,
mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"
version="1"
Flags="SerializationFormatter"/>

The demand was for:
<PermissionSet class="System.Security.PermissionSet"
version="1">
<IPermission class="System.Security.Permissions.SecurityPermission,
mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"
version="1"
Flags="SerializationFormatter"/>
</PermissionSet>

The granted set of the failing assembly was:
<PermissionSet class="System.Security.PermissionSet"
version="1">
<IPermission class="System.Security.Permissions.FileDialogPermission,
mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"
version="1"
Access="Open"/>
<IPermission
class="System.Security.Permissions.IsolatedStorageFilePermission, mscorlib,
Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"
version="1"
Allowed="ApplicationIsolationByUser"
UserQuota="512000"/>
<IPermission class="System.Security.Permissions.SecurityPermission,
mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"
version="1"
Flags="Execution"/>
<IPermission class="System.Security.Permissions.UIPermission, mscorlib,
Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"
version="1"
Window="SafeTopLevelWindows"
Clipboard="OwnClipboard"/>
<IPermission class="System.Security.Permissions.ZoneIdentityPermission,
mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"
version="1"
Zone="Internet"/>
<IPermission class="System.Drawing.Printing.PrintingPermission,
System.Drawing, Version=2.0.0.0, Culture=neutral,
PublicKeyToken=b03f5f7f11d50a3a"
version="1"
Level="SafePrinting"/>
<IPermission class="System.Security.Permissions.MediaPermission,
WindowsBase, Version=3.0.51116.0, Culture=neutral,
PublicKeyToken=31bf3856ad364e35"
version="1"
Audio="SafeAudio"
Video="SafeVideo"
Image="SafeImage"/>
<IPermission class="System.Security.Permissions.WebBrowserPermission,
WindowsBase, Version=3.0.51116.0, Culture=neutral,
PublicKeyToken=31bf3856ad364e35"
version="1"
Level="Safe"/>
</PermissionSet>

The assembly or AppDomain that failed was:
mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089

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