At first, this question is not the same as an question problem-with-logging, not the same becase that question/bug is an bug with FileLog (as is mentioned by Alex Yakunin).

Version: DataObjects.Net v4.3.5 (build 5872) for .NET 4.0

When i run unit test on my model, it throws me exception - Object reference not set to an instance of an object., stack trace:

   at Xtensive.Storage.Building.Builders.TypeBuilder.BuildType(TypeDef typeDef)
   at Xtensive.Storage.Building.Builders.ModelBuilder.BuildTypes(IEnumerable`1 typeDefs)
   at Xtensive.Storage.Building.Builders.ModelBuilder.BuildModel()
   at Xtensive.Storage.Building.Builders.ModelBuilder.Run()
   at Xtensive.Storage.Building.Builders.DomainBuilder.BuildModel()
   at Xtensive.Storage.Building.Builders.DomainBuilder.BuildDomain(DomainConfiguration configuration, DomainBuilderConfiguration builderConfiguration)
   at Xtensive.Storage.Upgrade.UpgradingDomainBuilder.BuildStageDomain(UpgradeStage stage)
   at Xtensive.Storage.Upgrade.UpgradingDomainBuilder.Build(DomainConfiguration configuration)
   at Xtensive.Storage.Domain.Build(DomainConfiguration configuration)
   at Model.Test.AutoBuildTest.BuildDomain(DomainConfiguration configuration) in c:\XYZ\AutoBuildTest.cs:line 39

I want to know what is wrong and thus trying to configure xtensive logging (as described in manual) but with no success. I am trying everything, finally my app.config looks like this:

  <configSections>
    <section name="Xtensive.Storage" type="Xtensive.Storage.Configuration.Elements.ConfigurationSection, Xtensive.Storage" />
    <section name="Xtensive.Core.Diagnostics" type="Xtensive.Core.Diagnostics.Configuration.ConfigurationSection, Xtensive.Core" />
  </configSections>

  <Xtensive.Core.Diagnostics>
    <logs>
      <!-- Use these settings for Xtensive.Storage.* logs -->
      <log name="Core" events="Debug,Info,Warning,Error,FatalError" provider="Console" />
      <log name="Modelling" events="Debug,Info,Warning,Error,FatalError" provider="Console"/>
      <log name="Storage.Building" events="Debug,Info,Warning,Error,FatalError" provider="Console"/>
      <log name="Storage" events="Debug,Info,Warning,Error,FatalError" provider="Console" />
      <log name="Storage.Providers.Sql" events="Debug,Info,Warning,Error,FatalError" provider="Console" />
    </logs>
  </Xtensive.Core.Diagnostics>

Also trying to change provider="Console" to provider="Debug" to see detailed report in debug window whats going on, but there are no debug writes from xtensive. Whats i must to configure to have debug writes?