Multiple Domains - One RT Instance

Is it possible to setup multiple LDAP/Active Directory domains to authenticate into the same RT server? I thought it would be as easy as adding an additional ExternalSettings block and naming it differently but no dice from what I see.

For anyone who has the same question as I did, it is possible, just without RT::LDAPImport.
See RT_SiteConfig.pm example below. Please note this is in a two domain Active Directory environment with email addresses being used in place of sAMAccountName.

Set($ExternalAuthPriority,  ['LDAP1','LDAP2']);
Set($ExternalInfoPriority,  ['LDAP1','LDAP2']);

Set($ExternalSettings, 
{
'LDAP1'         =>  {
'type'            =>  'ldap',
'server'          =>  '10.***.***.***',
'user'            =>  '****',
'pass'            =>  '****',
'base'            =>  'DC=LDAP1,DC=com',
'filter'          => '(objectClass=person)',
'tls'             => 0,
'ssl_version'     => 3, 
'net_ldap_args'   =>  [ version => 3 ],
'attr_match_list' => ['EmailAddress'],
'attr_map' => { 'Name' => 'mail',
'EmailAddress' => 'mail',
'Organization' => 'physicalDeliveryOfficeName',
'RealName' => 'displayName',
'Gecos' => 'sAMAccountName',
'WorkPhone' => 'telephoneNumber',
'Address1' => 'description',
'City' => 'l',
'State' => 'st',
'Zip' => 'postalCode',
'Country' => 'co'
}
},
'LDAP2'         =>  {
'type'            =>  'ldap',
'server'          =>  '10.***.***.***',
'user'            =>  '****',
'pass'            =>  '****',
'base'            =>  'DC=LDAP2,DC=com',
'filter'          => '(objectClass=person)',
'tls'             => 0,
'ssl_version'     => 3,
'net_ldap_args'   =>  [ version => 3 ],
'attr_match_list' => ['EmailAddress'],
'attr_map' => { 'Name' => 'mail',
'EmailAddress' => 'mail',
'Organization' => 'physicalDeliveryOfficeName',
'RealName' => 'displayName',
'Gecos' => 'sAMAccountName',
'WorkPhone' => 'telephoneNumber',
'Address1' => 'description',
'City' => 'l',
'State' => 'st',
'Zip' => 'postalCode',
'Country' => 'co'
}
}
} );