Trying to migrate Date values using migrate module.
At the base there was a problem: the module dates was patched.
The final code that have worked:

my.info

dependencies[] = migrate
dependencies[] = migrate_extras
dependencies[] = date
dependencies[] = date_migrate


my.make

projects[migrate][subdir] = "contrib"
projects[migrate][version] = "2.6-rc1"
projects[migrate_extras][subdir] = "contrib" 
projects[migrate_extras][version] = "2.5"
projects[date][subdir] = "contrib"
projects[date][version] = "2.6"
projects[date][patch][] = "https://drupal.org/files/date-consolidated_migrate-1.patch"


my_migration.inc

$this-&gt;addFieldMapping('field_date', 'date_from');
$this-&gt;addFieldMapping('field_date:to', 'date_to');
$this-&gt;addFieldMapping('field_date:timezone', 'UTC');