diff --git a/sharethis.module b/sharethis.module
index 3ac3aa3..8b8486f 100644
--- a/sharethis.module
+++ b/sharethis.module
@@ -348,7 +348,7 @@ function sharethis_node_view($node, $view_mode, $langcode) {
           $node->content['sharethis'] = array(
             '#tag' => 'div', // Wrap it in a div.
             '#type' => 'html_tag',
-            '#attributes' => array('class' => 'sharethis-buttons'),
+            '#attributes' => array('class' => array('sharethis-buttons')),
             '#value' => sharethis_get_button_HTML($data_options, $mPath, $mTitle),
             '#weight' => intval(variable_get('sharethis_weight', 10)),
           );
@@ -357,7 +357,7 @@ function sharethis_node_view($node, $view_mode, $langcode) {
           $links['sharethis'] = array(
             'html' => TRUE,
             'title' => sharethis_get_button_HTML($data_options, $mPath, $mTitle),
-            'attributes' => array('class' => 'sharethis-buttons'),
+            'attributes' => array('class' => array('sharethis-buttons')),
           );
           $node->content['links']['sharethis'] = array(
             '#theme' => 'links',