Branch Tag not a branch tag

[petesea]

I have a CVS tree that when checked out to an empty directory using a 
branch tag, forces SOME directories in the tree to a non-branch tag.  How 
can this happen and how do I fix it?

As a simple example, I do:

  $ cvs co -r foo_branch tree
  (no errors/warnings during checkout)

When I look at the CVS/Tag files for all the dirs in the working copy I 
get:

  tree/dir1/CVS/Tag: Tfoo_branch
  tree/dir2/CVS/Tag: Nfoo_branch
  tree/dir3/CVS/Tag: Tfoo_branch
  tree/dir3/dir3_1/CVS/Tag: Tfoo_branch
  tree/dir3/dir3_2/CVS/Tag: Nfoo_branch
  tree/dir4/CVS/Tag: Tfoo_branch
  tree/dir4/dir4_1/CVS/Tag: Nfoo_branch
  tree/dir4/dir4_1/dir4_1_1/CVS/Tag: Tfoo_branch
  tree/dir4/dir4_1/dir4_1_2/CVS/Tag: Tfoo_branch

In other words... while most of the dirs are marked as a branch tag 
(Tfoo_branch) 3 of the dirs are marked as a non-branch tag (Nfoo_branch).

If I look at the CVS/Entries file for the 3 dirs where the CVS/Tag file 
contains "Nfoo_branch", all the files are marked as "Tfoo_branch".