diff --git includes/theme.inc includes/theme.inc
index 4bf80d8..d3236f1 100644
--- includes/theme.inc
+++ includes/theme.inc
@@ -1754,10 +1754,10 @@ function theme_table($variables) {
  */
 function theme_tablesort_indicator($variables) {
   if ($variables['style'] == "asc") {
-    return theme('image', array('path' => 'misc/arrow-asc.png', 'alt' => t('sort ascending'), 'title' => t('sort ascending')));
+    return theme('image', array('path' => 'misc/arrow-asc.png', 'width' => 13, 'height' => 13, 'alt' => t('sort ascending'), 'title' => t('sort ascending')));
   }
   else {
-    return theme('image', array('path' => 'misc/arrow-desc.png', 'alt' => t('sort descending'), 'title' => t('sort descending')));
+    return theme('image', array('path' => 'misc/arrow-desc.png', 'width' => 13, 'height' => 13, 'alt' => t('sort descending'), 'title' => t('sort descending')));
   }
 }
 
@@ -1869,7 +1869,7 @@ function theme_more_help_link($variables) {
  */
 function theme_feed_icon($variables) {
   $text = t('Subscribe to @feed-title', array('@feed-title' => $variables['title']));
-  if ($image = theme('image', array('path' => 'misc/feed.png', 'alt' => $text))) {
+  if ($image = theme('image', array('path' => 'misc/feed.png', 'width' => 16, 'height' => 16, 'alt' => $text))) {
     return l($image, $variables['url'], array('html' => TRUE, 'attributes' => array('class' => array('feed-icon'), 'title' => $text)));
   }
 }
diff --git modules/simpletest/simpletest.pages.inc modules/simpletest/simpletest.pages.inc
index f02304e..42cf1f6 100644
--- modules/simpletest/simpletest.pages.inc
+++ modules/simpletest/simpletest.pages.inc
@@ -83,8 +83,8 @@ function theme_simpletest_test_table($variables) {
   // Define the images used to expand/collapse the test groups.
   $js = array(
     'images' => array(
-      theme('image', array('path' => 'misc/menu-collapsed.png', 'alt' => t('Expand'), 'title' => t('Expand'))) . ' <a href="#" class="simpletest-collapse">(' . t('Expand') . ')</a>',
-      theme('image', array('path' => 'misc/menu-expanded.png', 'alt' => t('Collapse'), 'title' => t('Collapse'))) . ' <a href="#" class="simpletest-collapse">(' . t('Collapse') . ')</a>',
+      theme('image', array('path' => 'misc/menu-collapsed.png', 'width' => 7, 'height' => 7, 'alt' => t('Expand'), 'title' => t('Expand'))) . ' <a href="#" class="simpletest-collapse">(' . t('Expand') . ')</a>',
+      theme('image', array('path' => 'misc/menu-expanded.png', 'width' => 7, 'height' => 7, 'alt' => t('Collapse'), 'title' => t('Collapse'))) . ' <a href="#" class="simpletest-collapse">(' . t('Collapse') . ')</a>',
     ),
   );
 
@@ -427,10 +427,10 @@ function simpletest_result_status_image($status) {
 
   if (!isset($map)) {
     $map = array(
-      'pass' => theme('image', array('path' => 'misc/watchdog-ok.png', 'alt' => t('Pass'))),
-      'fail' => theme('image', array('path' => 'misc/watchdog-error.png', 'alt' => t('Fail'))),
-      'exception' => theme('image', array('path' => 'misc/watchdog-warning.png', 'alt' => t('Exception'))),
-      'debug' => theme('image', array('path' => 'misc/watchdog-warning.png', 'alt' => t('Debug'))),
+      'pass' => theme('image', array('path' => 'misc/watchdog-ok.png', 'width' => 18, 'height' => 18, 'alt' => t('Pass'))),
+      'fail' => theme('image', array('path' => 'misc/watchdog-error.png', 'width' => 18, 'height' => 18, 'alt' => t('Fail'))),
+      'exception' => theme('image', array('path' => 'misc/watchdog-warning.png', 'width' => 18, 'height' => 18, 'alt' => t('Exception'))),
+      'debug' => theme('image', array('path' => 'misc/watchdog-warning.png', 'width' => 18, 'height' => 18, 'alt' => t('Debug'))),
     );
   }
   if (isset($map[$status])) {
diff --git modules/update/update.report.inc modules/update/update.report.inc
index ca33cf1..70af016 100644
--- modules/update/update.report.inc
+++ modules/update/update.report.inc
@@ -58,25 +58,25 @@ function theme_update_report($variables) {
     switch ($project['status']) {
       case UPDATE_CURRENT:
         $class = 'ok';
-        $icon = theme('image', array('path' => 'misc/watchdog-ok.png', 'alt' => t('ok'), 'title' => t('ok')));
+        $icon = theme('image', array('path' => 'misc/watchdog-ok.png', 'width' => 18, 'height' => 18, 'alt' => t('ok'), 'title' => t('ok')));
         break;
       case UPDATE_UNKNOWN:
       case UPDATE_FETCH_PENDING:
       case UPDATE_NOT_FETCHED:
         $class = 'unknown';
-        $icon = theme('image', array('path' => 'misc/watchdog-warning.png', 'alt' => t('warning'), 'title' => t('warning')));
+        $icon = theme('image', array('path' => 'misc/watchdog-warning.png', 'width' => 18, 'height' => 18, 'alt' => t('warning'), 'title' => t('warning')));
         break;
       case UPDATE_NOT_SECURE:
       case UPDATE_REVOKED:
       case UPDATE_NOT_SUPPORTED:
         $class = 'error';
-        $icon = theme('image', array('path' => 'misc/watchdog-error.png', 'alt' => t('error'), 'title' => t('error')));
+        $icon = theme('image', array('path' => 'misc/watchdog-error.png', 'width' => 18, 'height' => 18, 'alt' => t('error'), 'title' => t('error')));
         break;
       case UPDATE_NOT_CHECKED:
       case UPDATE_NOT_CURRENT:
       default:
         $class = 'warning';
-        $icon = theme('image', array('path' => 'misc/watchdog-warning.png', 'alt' => t('warning'), 'title' => t('warning')));
+        $icon = theme('image', array('path' => 'misc/watchdog-warning.png', 'width' => 18, 'height' => 18, 'alt' => t('warning'), 'title' => t('warning')));
         break;
     }
 
diff --git themes/seven/template.php themes/seven/template.php
index 78d41f1..1a726c5 100644
--- themes/seven/template.php
+++ themes/seven/template.php
@@ -85,10 +85,10 @@ function seven_tablesort_indicator($variables) {
   $style = $variables['style'];
   $theme_path = drupal_get_path('theme', 'seven');
   if ($style == 'asc') {
-    return theme('image', array('path' => $theme_path . '/images/arrow-asc.png', 'alt' => t('sort ascending'), 'title' => t('sort ascending')));
+    return theme('image', array('path' => $theme_path . '/images/arrow-asc.png', 'alt' => t('sort ascending'), 'width' => 13, 'height' => 13, 'title' => t('sort ascending')));
   }
   else {
-    return theme('image', array('path' => $theme_path . '/images/arrow-desc.png', 'alt' => t('sort descending'), 'title' => t('sort descending')));
+    return theme('image', array('path' => $theme_path . '/images/arrow-desc.png', 'alt' => t('sort descending'), 'width' => 13, 'height' => 13, 'title' => t('sort descending')));
   }
 }