diff --git a/src/IDF/Migrations/17DownloadMD5.php b/src/IDF/Migrations/17DownloadMD5.php
index 34e030f..3b86bc2 100644
--- a/src/IDF/Migrations/17DownloadMD5.php
+++ b/src/IDF/Migrations/17DownloadMD5.php
@@ -27,20 +27,29 @@
 
 function IDF_Migrations_17DownloadMD5_up($params=null)
 {
+    // Add the row
     $table = Pluf::factory('IDF_Upload')->getSqlTable();
     $sql = array();
-    $sql['PostgreSQL'] = 'ALTER TABLE '.$table.' ADD COLUMN "md5" TEXT DEFAULT \'\'';
-    $sql['MySQL'] = 'ALTER TABLE '.$table.' ADD COLUMN `md5` LONGTEXT DEFAULT \'\'';
+    $sql['PostgreSQL'] = 'ALTER TABLE '.$table.' ADD COLUMN "md5" VARCHAR(32) DEFAULT \'\'';
+    $sql['MySQL'] = 'ALTER TABLE '.$table.' ADD COLUMN `md5` VARCHAR(32) DEFAULT \'\'';
     $db = Pluf::db();
     $engine = Pluf::f('db_engine');
     if (!isset($sql[$engine])) {
         throw new Exception('SQLite complex migration not supported.');
     }
     $db->execute($sql[$engine]);
+    
+    // Process md5 of already uploaded file
+    $files = Pluf::factory('IDF_Upload')->getList();
+    foreach ($files as $f) {
+        $f->md5 = md5_file (Pluf::f('upload_path') . '/' . $f->get_project()->shortname . '/files/' . $f->file);
+        $f->update();
+    }
 }
 
 function IDF_Migrations_17DownloadMD5_down($params=null)
 {
+    // Remove the row
     $table = Pluf::factory('IDF_Upload')->getSqlTable();
     $sql = array();
     $sql['PostgreSQL'] = 'ALTER TABLE '.$table.' DROP COLUMN "md5"';
@@ -51,5 +60,4 @@ function IDF_Migrations_17DownloadMD5_down($params=null)
         throw new Exception('SQLite complex migration not supported.');
     }
     $db->execute($sql[$engine]);
-
 }