Problem: product names can be up to 128 characters in length in the database (products_description table: products_name)
However the default limit on the number of characters displayed in the Categories & Products area in the Admin is only 64. If you have product titles that are longer than this, you need to change this default.
Line 1880 <td class="main"><?php echo tep_draw_input_field('products_name [' . $languages[$i]['id'] . ']', $products_name_field, 'size="64" maxlength="XXX"'); ?></td>
Change the ‘xxx’ value to any number of characters up to 129.