NAnt problem after upgrading to .NET 4.0

I have been using NAnt 0.91-alpha2 on our Server 2003 Standard Edition
server to manage several of our build tasks, yesterday I upgraded to
.NET 4.0 via windows update and I am now getting an error when I try
to run NAnt, even if I open up a console window and just try running
"nant.exe" with no arguments I am getting an error.  I also confirmed
the same thing is happening on my Windows XP development box.  On my
XP machine I got the following error:

C:\Program Files\nant-0.91-alpha2\bin>nant.exe

Unhandled Exception: System.TypeInitializationException: The type
initializer for 'NAnt.Console.ConsoleStub' threw an exception. --->
System.Security.SecurityException: Request for the permission of type
'System.Security.Permissions.FileIOPermission, mscorlib,
Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'
failed.
   at System.Security.CodeAccessSecurityEngine.Check(Object demand,
StackCrawlMark& stackMark, Boolean isPermSet)
   at System.Security.CodeAccessSecurityEngine.Check(CodeAccessPermission
cap, StackCrawlMark& stackMark)
   at System.Security.CodeAccessPermission.Demand()
   at System.AppDomainSetup.VerifyDir(String dir, Boolean normalize)
   at System.AppDomain.get_BaseDirectory()
   at log4net.Config.XmlConfiguratorAttribute.Configure(Assembly
sourceAssembly, ILoggerRepository targetRepository)
   at log4net.Core.DefaultRepositorySelector.ConfigureRepository(Assembly
assembly, ILoggerRepository repository)
   at log4net.Core.DefaultRepositorySelector.CreateRepository(Assembly
repositoryAssembly, Type repositoryType, String repositoryName,
Boolean readAssemblyAttributes)
   at log4net.Core.DefaultRepositorySelector.CreateRepository(Assembly
repositoryAssembly, Type repositoryType)
   at log4net.Core.DefaultRepositorySelector.GetRepository(Assembly
repositoryAssembly)
   at log4net.Core.LoggerManager.GetLogger(Assembly
repositoryAssembly, String name)
   at log4net.LogManager.GetLogger(Assembly repositoryAssembly, String name)
   at log4net.LogManager.GetLogger(Type type)
   at NAnt.Console.ConsoleStub..cctor()
   --- End of inner exception stack trace ---
   at NAnt.Console.ConsoleStub.Main(String[] args)

C:\Program Files\nant-0.91-alpha2\bin>

So everything was working fine using .NET 3.5, but as soon as I
upgraded to .NET 4.0 I get the error I referenced above.  Any
suggestions on what could be causing this?  Also I confirmed that I am
getting the same error when I tried running the nightly build
(nant-0.91-nightly-2010-05-12).

Thank You.
-- 
Marcus Weidner
www.KD8ITX.com

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