The description for the pathdepth option for addurl doesn't match its behaviour (emphasis mine).

Rather than basing the filename on the whole url, this causes a path to be constructed, starting at the specified depth within the path of the url.

For example, adding the url http://www.example.com/dir/subdir/bigfile with --pathdepth=1 will use "dir/subdir/bigfile", while --pathdepth=3 will use "bigfile".

This isn't how it behaves. It would be more accurate as (emphasis on changes):

Rather than basing the filename on the whole url, this causes a filename to be constructed, starting at the specified depth within the path of the url.

For example, adding the url http://www.example.com/dir/subdir/bigfile with --pathdepth=1 will use "dir_subdir_bigfile", while --pathdepth=3 will use "bigfile".

For what I am doing (adding a directory tree with addurl and file:// URLs), I'd actually like the behaviour described (to recreate the tree), but I'm not sure which one was the intended behaviour..

done; bug report didn't show what was wrong; I can see nothing wrong; bug reporter cannot seem to remember what was wrong. Probably user error. --Joey