Warning: Illegal string offset 'tag_id'

[masche842]

As already noted in punbb/punbb#125 I've upgraded an existing punBB installation to 1.4.2 and get a warning message when trying to split posts into new topics.

The original message is:

Warning: Illegal string offset 'tag_id' in .../htdocs/forum/moderate.php(386) : eval()'d code on line 18

which leads to extensions/pun_tag/manifest.xml:

                    if ($fid)
                    {
                            $res_tags = array();
                            if (isset($pun_tags['topics'][$tid]))
                            {

                                    foreach ($pun_tags['topics'][$tid] as $tag_id)
                                            foreach ($pun_tags['index'] as $tag)
                                                    if ($tag['tag_id'] == $tag_id)
                                                            $res_tags[] = $tag['tag'];
                            }

                            ?>
                            <div class="sf-box text">
                                            <label for="fld<?php echo ++$forum_page['fld_count'] ?>"><span><?php echo $lang_pun_tags['Topic tags']; ?></span><small><?php echo $lang_pun_tags['Enter tags']; ?></small></label><br />
                                            <span class="fld-input"><input id="fld<?php echo $forum_page['fld_count'] ?>" type="text" name="pun_tags" value="<?php if (!empty($res_tags)) echo implode(', ', $res_tags); else echo '';  ?>" size="70" maxlength="100"/></span>
                            </div>
                    <?php

                    }

Does anyone have a clue what's going on there?