first import

sites/all/modules/migrate/migrate.mail.inc

@@ -0,0 +1,23 @@
+<?php
+
+/**
+ * @file
+ * Null-op mail class, to keep migration from spamming innocent users.
+ */
+
+class MigrateMailIgnore extends DefaultMailSystem {
+  /**
+   * On an email request, do nothing and say we did.
+   *
+   * @see http://php.net/manual/en/function.mail.php
+   * @see drupal_mail()
+   *
+   * @param $message
+   *   A message array, as described in hook_mail_alter().
+   * @return
+   *   TRUE if the mail was successfully accepted, otherwise FALSE.
+   */
+  public function mail(array $message) {
+    return TRUE;
+  }
+}