Date stamp appears for nodes that shouldn't display author info

See #350546: Selectable Content Types for Author Taxonomy (comments #5 and #6) for the original report from saccard. Here's a summary:

I have tested the new release on my test site (drupal 5.14 with author taxonomy 5.1.2). But the date stamp from author taxonomy ist still visible on all pages, regardless of the content type of the page. The category which is used by Author taxonomy belongs only to one content type and the author's name is correctly displayd only on the pages of this content type.

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okay, this little modifications solves the problem (on my test site).
in author_taxonomy.module I changed line 275 from

if ($show_timestamp) {

to

if ($show_timestamp && !empty($author_names)) {