Assembly version was not updated during compile. Related discussion: http://npanday.codeplex.com/Thread/View.aspx?ThreadId=215098
Apart from the issue mentioned in the discussion in the patch functionality for injecting build number (through BUILD_NUMBER environment variable) has been implemented. Although this is not related to the main issue but in this way AssemblyVersion, AssemblyFileVersion and AssemblyInformationlVersion updating during compile will be complete. If BUILD_NUMBER is not set there won't be any error.
I created a patch for it (see attachement)