Index: modules/system/system.admin.inc
===================================================================
RCS file: /cvs/drupal/drupal/modules/system/system.admin.inc,v
retrieving revision 1.298
diff -u -r1.298 system.admin.inc
--- modules/system/system.admin.inc	22 Aug 2010 12:55:04 -0000	1.298
+++ modules/system/system.admin.inc	1 Sep 2010 23:13:28 -0000
@@ -866,6 +866,7 @@
       $extra['required_by'][] = $distribution_name;
     }
 
+    $extra['states']['requires'] = array();
     // If this module requires other modules, add them to the array.
     foreach ($module->requires as $requires => $v) {
       if (!isset($files[$requires])) {
@@ -889,6 +890,7 @@
           $extra['requires'][$requires] = t('@module (<span class="admin-disabled">disabled</span>)', array('@module' => $requires_name));
         }
       }
+      $extra['states']['requires'][] = array('package' => $files[$requires]->info['package'], 'filename' => $requires);
     }
     // Generate link for module's help page, if there is one.
     if ($help_arg && $module->status && in_array($filename, module_implements('help'))) {
@@ -924,8 +926,7 @@
       }
     }
 
-    // Mark dependents disabled so the user cannot remove required modules.
-    $dependents = array();
+    $extra['states']['required_by'] = array();
     // If this module is required by other modules, list those, and then make it
     // impossible to disable this one.
     foreach ($module->required_by as $required_by => $v) {
@@ -938,6 +939,7 @@
         else {
           $extra['required_by'][] = t('@module (<span class="admin-disabled">disabled</span>)', array('@module' => $files[$required_by]->info['name']));
         }
+        $extra['states']['required_by'][] = array('package' => $files[$required_by]->info['package'], 'filename' => $required_by);
       }
     }
     $form['modules'][$module->info['package']][$filename] = _system_modules_build_row($module->info, $extra);
@@ -1040,6 +1042,14 @@
     $status_long .= t('This module requires PHP version @php_required and is incompatible with PHP version !php_version.', array('@php_required' => $php_required, '!php_version' => phpversion()));
   }
 
+  $states = array();
+  foreach ($extra['states']['requires'] as $requires) {
+    $states[':input[name="modules[' . $requires['package'] . '][' . $requires['filename'] . '][enable]"]'] = array('checked' => TRUE);
+  }
+  foreach ($extra['states']['required_by'] as $required_by) {
+    $states[':input[name="modules[' . $required_by['package'] . '][' . $required_by['filename'] . '][enable]"]'] = array('checked' => FALSE);
+  }
+
   // If this module is compatible, present a checkbox indicating
   // this module may be installed. Otherwise, show a big red X.
   if ($compatible) {
@@ -1047,6 +1057,9 @@
       '#type' => 'checkbox',
       '#title' => t('Enable'),
       '#default_value' => $extra['enabled'],
+      '#states' => array(
+        'enabled' => $states,
+      ),
     );
     if ($extra['disabled']) {
       $form['enable']['#disabled'] = TRUE;
@@ -1123,7 +1136,6 @@
 
   // Builds list of modules.
   $modules = array();
-  // If we're not coming from the confirmation form, build the list of modules.
   if (empty($form_state['storage'])) {
     // If we're not coming from the confirmation form, build the module list.
     foreach ($form_state['values']['modules'] as $group_name => $group) {