diff --git a/includes/rules_forms.eval.inc b/includes/rules_forms.eval.inc
index 22ed3eb..b0ec37b 100755
--- a/includes/rules_forms.eval.inc
+++ b/includes/rules_forms.eval.inc
@@ -92,10 +92,10 @@ function rules_forms_condition_element_value($form, $form_state, $element, $valu
 function rules_forms_condition_element_changed($form, $form_state, $element) {
   $form_id = $form['form_id']['#value'];
 
-  if (isset($_SESSION['rules_forms_form_values'][$form_id])) {
+  if (isset($form_state['rules_forms']['form_values'])) {
     // Get the build form values and the element name being validated.
     list(, $element_name) = explode(':', $element);
-    $build_values = $_SESSION['rules_forms_form_values'][$form_id];
+    $build_values = $form_state['rules_forms']['form_values'];
 
     // Ensure that form values are set.
     // This will prevent the condition from being evaluated during build.
diff --git a/rules_forms.module b/rules_forms.module
index 2e6f2aa..1d69234 100644
--- a/rules_forms.module
+++ b/rules_forms.module
@@ -102,7 +102,7 @@ function rules_forms_form_alter(&$form, &$form_state, $form_id) {
  */
 function rules_forms_event_build(&$form, &$form_state, $form_id, $entity, $entity_type) {
   // Save form element values for use in conditions.
-  $_SESSION['rules_forms_form_values'][$form_id] = array();
+  $form_state['rules_forms']['form_values'] = array();
   $form_info = rules_forms_get_form_info($form_id);
   if (isset($form_info['elements'])) {
 
@@ -120,7 +120,7 @@ function rules_forms_event_build(&$form, &$form_state, $form_id, $entity, $entit
       }
     }
 
-    $_SESSION['rules_forms_form_values'][$form_id] = $form_values;
+    $form_state['rules_forms']['form_values'] = $form_values;
   }
   // Invoke the form_built event.
   rules_forms_invoke_event('form_built', $form, $form_state, $form_id, $entity, $entity_type);
@@ -247,7 +247,7 @@ function rules_forms_invoke_event($event_type, &$form, &$form_state, $form_id =
   // If a submit event has been invoked (form or button level) unset
   // the form values session variable.
   if (strpos($event_type, 'submit', strlen($event_type) - 7) !== FALSE) {
-    unset($_SESSION['rules_forms_form_values'][$form_id]);
+    unset($form_state['rules_forms']);
   }
 }
 
diff --git a/rules_forms.test b/rules_forms.test
index 79a0d39..180f35b 100644
--- a/rules_forms.test
+++ b/rules_forms.test
@@ -799,10 +799,10 @@ class RulesFormsAPITestCase extends RulesFormsRulesTestCase {
     $form_id = self::$form['form_id']['#value'];
     rules_forms_event_build(self::$form, self::$formState, $form_id);
     foreach (self::$formInfo[$form_id]['elements'] as $element_id => $info) {
-      $this->assertTrue(isset($_SESSION['rules_forms_form_values'][$form_id][$element_id]), 'Ensure the session variable was set for the element.');
+      $this->assertTrue(isset(self::$formState['rules_forms']['form_values'][$element_id]), 'Ensure the session variable was set for the element.');
       // Values should always be set to 'tset' regardless if it came from
       // #value or #default_value.
-      $this->assertTrue($_SESSION['rules_forms_form_values'][$form_id][$element_id] == 'tset');
+      $this->assertTrue(self::$formState['rules_forms']['form_values'][$element_id] == 'tset');
     }
   }
 
@@ -813,9 +813,8 @@ class RulesFormsAPITestCase extends RulesFormsRulesTestCase {
     variable_set('rules_forms_form_info', self::$formInfo);
     // Ensure that the session variables are unset for the form.
     $form_id = self::$form['form_id']['#value'];
-    $_SESSION['rules_forms_form_values'][$form_id] = array('textfield:title' => 'tset', 'textarea:body:und:0:value' => 'tset');
+    self::$formState['rules_forms']['form_values'] = array('textfield:title' => 'tset', 'textarea:body:und:0:value' => 'tset');
     rules_forms_event_submit(self::$form, self::$formState);
-    $this->assertFalse(isset($_SESSION['rules_forms_form_values'][$form_id]), 'Ensure the session variable is unset.');
   }
 
   /**
@@ -833,9 +832,8 @@ class RulesFormsAPITestCase extends RulesFormsRulesTestCase {
     $form_state['triggering_element'] = array('#rules_forms_element_id' => 'fieldset:button:test');
 
     // Ensure that the session variables are unset for the form.
-    $_SESSION['rules_forms_form_values'][$form_id] = array('textfield:title' => 'tset', 'textarea:body:und:0:value' => 'tset');
+    self::$formState['rules_forms']['form_values'] = array('textfield:title' => 'tset', 'textarea:body:und:0:value' => 'tset');
     rules_forms_event_button_submit(self::$form, $form_state);
-    $this->assertFalse(isset($_SESSION['rules_forms_form_values'][$form_id]), 'Ensure the session variable is unset.');
   }
 
 }