In case someone else is looking...

The default Drupal users table has a column called data which stores a serialized array of fields and values. This data field isn't included with the normal fields provided by MigrateDestinationUser::getKeySchema() and I wasn't able to find any documentation for migrate that demonstrated how to populate this field. I dug around in the code and after a little trial and error came up with the following function which should be added in your user migration class:

<?php
public function prepare(stdClass $account, stdClass $row) {
 
$account->data = array('field1' => 1, 'field2' => 2);
}
?>

Comments

Component:Code» Documentation
Status:Active» Fixed

This is the simplest way to migrate the 'data' data:

<?php
    $this
->addFieldMapping('data', 'data')
         ->
callbacks('unserialize');
?>

The best place to add hints and tips would be under http://drupal.org/node/1007002, not in the issue queue.

Status:Fixed» Closed (fixed)

Automatically closed -- issue fixed for 2 weeks with no activity.