Ron Parker said: "This same exact code worked in 5.x, so I have to believe there is something that has changed in 6.x with module_invoke() / $user . Furthermore, this code worked in the initial Drupal 6.x versions, so this change, whatever it is, is rather recent. Theoretically, module_invoke below should not return false, but it is"

  Nancy Wichmann said: "I have recently run into problems with hook_access. It is widely misunderstood and many module return false when they really should be returning null.  I  even had to change many of my modules.  I know there are many out there that are still wrong."

Could someone please point me to how I begin to solve this problem?  I am certain that the user object contains the correct roles that should allow permission. How do I track down what's going on with module_invoke?

-ron