diff --git a/library/Director/Data/Db/DbObject.php b/library/Director/Data/Db/DbObject.php
index a8d684a7..283f4bd9 100644
--- a/library/Director/Data/Db/DbObject.php
+++ b/library/Director/Data/Db/DbObject.php
@@ -183,6 +183,7 @@ abstract class DbObject
      */
     protected function onDelete() {}
 
+
     /**
      * Set DB adapter
      *
@@ -245,7 +246,9 @@ abstract class DbObject
     public function set($key, $value)
     {
         $key = (string) $key;
-
+        if ($value === '') {
+            $value = null;
+        }
         if (! $this->hasProperty($key)) {
             throw new Exception(sprintf('Trying to set invalid key %s', $key));
         }