diff --git a/includes/commerce.controller.inc b/includes/commerce.controller.inc
index b29ddb9..6223903 100644
--- a/includes/commerce.controller.inc
+++ b/includes/commerce.controller.inc
@@ -57,6 +57,14 @@ interface DrupalCommerceEntityControllerInterface extends EntityAPIControllerInt
    */
   public function releaseLock($entity);
 
+  /**
+   * Register the given entity as to be locked.
+   *
+   * @param object $entity
+   *   The entity to lock.
+   */
+  public function setLock($entity);
+
 }
 
 /**
@@ -153,7 +161,13 @@ class DrupalCommerceEntityController extends DrupalDefaultEntityController imple
    * The transaction is not necessarily committed immediately. Drupal will
    * commit it as soon as possible given the state of the transaction stack.
    */
-  protected function releaseLocks() {
+  protected function releaseLocks($ids = array()) {
+    if (is_array($ids) && !empty($ids)) {
+      foreach ($ids as $id) {
+        unset($this->lockedEntities[$id]);
+      }
+    }
+
     if (empty($this->lockedEntities)) {
       $this->controllerTransaction = NULL;
     }
@@ -170,6 +184,27 @@ class DrupalCommerceEntityController extends DrupalDefaultEntityController imple
   }
 
   /**
+   * Implements DrupalCommerceEntityControllerInterface::setLock().
+   */
+  public function setLock($entity) {
+    $this->setLocks(array($entity->{$this->idKey}));
+  }
+
+  /**
+   * Lock the given entities IDs
+   *
+   * @param array $ids
+   *  Ids of the entities to be locked.
+   */
+  protected function setLocks($ids) {
+    foreach ($ids as $id) {
+      if ($id) {
+        $this->lockedEntities[$id] = TRUE;
+      }
+    }
+  }
+
+  /**
    * Overrides DrupalDefaultEntityController::load().
    *
    * Accepts a condition of locking request, may not necessarily take effect
@@ -182,15 +217,24 @@ class DrupalCommerceEntityController extends DrupalDefaultEntityController imple
     $this->requestLocking = $conditions['_lock'];
     unset($conditions['_lock']);
 
+    $require_locking =  $this->requireLocking();
+
     // If locking has been required, then bypass the internal cache for any
     // entities that are not already locked.
-    if ($this->requireLocking()) {
-      foreach (array_diff_key(array_flip($ids), $this->lockedEntities) as $id => $value) {
-        unset($this->entityCache[$id]);
-      }
+    if ($require_locking) {
+      $non_locked = array_diff_key(array_flip($ids), $this->lockedEntities);
+      $this->resetCache(array_keys($non_locked));
     }
 
-    return parent::load($ids, $conditions);
+    // Load the required entities.
+    $loaded = parent::load($ids, $conditions);
+
+    // // If locking has been required then lock the loaded entities.
+    if ($require_locking && $loaded && !empty($loaded)) {
+      $this->setLocks(array_keys($loaded));
+    }
+
+    return $loaded;
   }
 
   /**
@@ -210,12 +254,6 @@ class DrupalCommerceEntityController extends DrupalDefaultEntityController imple
       }
 
       $query->forUpdate();
-
-      // Store the ids of the entities in the lockedEntities array for later
-      // tracking, flipped for easier management via unset() below.
-      if (is_array($ids)) {
-        $this->lockedEntities += array_flip($ids);
-      }
     }
 
     return $query;
@@ -279,11 +317,8 @@ class DrupalCommerceEntityController extends DrupalDefaultEntityController imple
       // Reset the cache as soon as the changes have been applied.
       $this->resetCache($ids);
 
-      // Maintain the list of locked entities and release the lock if possible.
-      foreach ($ids as $id) {
-        unset($this->lockedEntities[$id]);
-      }
-      $this->releaseLocks();
+      // Release the lock if possible.
+      $this->releaseLocks($ids);
 
       foreach ($entities as $id => $entity) {
         $this->invoke('delete', $entity);
@@ -379,10 +414,9 @@ class DrupalCommerceEntityController extends DrupalDefaultEntityController imple
 
       // Update the static cache so that the next entity_load() will return this
       // newly saved entity.
-      $this->entityCache[$entity->{$this->idKey}] = $entity;
+      $this->cacheSet(array($entity->{$this->idKey} => $entity));
 
-      // Maintain the list of locked entities and release the lock if possible.
-      unset($this->lockedEntities[$entity->{$this->idKey}]);
+      // Release the lock.
       $this->releaseLock($entity);
 
       $this->invoke($op, $entity);