diff --git a/lib/Doctrine/Connection.php b/lib/Doctrine/Connection.php
index a5e5042b2..9b7c29705 100644
--- a/lib/Doctrine/Connection.php
+++ b/lib/Doctrine/Connection.php
@@ -469,7 +469,10 @@ abstract class Doctrine_Connection extends Doctrine_Configurable implements Coun
             return false;
         }
         // column names are specified as array keys
-        $cols = array_keys($values);
+        $cols = array();
+        foreach ($values as $key => $value) {
+            $cols[] = $this->quoteIdentifier($key);
+        }
 
         // build the statement
         $query = 'INSERT INTO ' . $this->quoteIdentifier($table) 
diff --git a/lib/Doctrine/Transaction.php b/lib/Doctrine/Transaction.php
index edec8cf96..628285aef 100644
--- a/lib/Doctrine/Transaction.php
+++ b/lib/Doctrine/Transaction.php
@@ -129,17 +129,9 @@ class Doctrine_Transaction extends Doctrine_Connection_Module
      */
     public function addInvalid(Doctrine_Record $record)
     {
-        /**
-         * for some weird reason in_array cannot be used here (php bug ?)
-         *
-         * if used it results in fatal error : [ nesting level too deep ]
-         */
-        foreach ($this->invalid as $val) {
-            if ($val === $record) {
-                return false;
-            }
+        if (in_array($record, $this->invalid, true)) {
+            return false;
         }
-
         $this->invalid[] = $record;
         return true;
     }