Converting 4.0.x modules to 4.1.x

Drupal 4.1 changed the block hook function and taxonomy API. To convert a version 4.0 module to 4.1, the following changes must be made. First, the *_block() function must be re-written. Next, calls to taxonomy_get_tree() must be re-written to supply the parameters required by the new function. Finally, you may wish to take advantage of new functions added to the taxonomy API.