Geocoding using Ziptable fails/throws errors

Let me set the stage:
Drupal 4.7.3, CiviCRM 1.5 rev 6927, PHP 5.0.4
Presumably other versions are affected too.

civicrm.settings.php, 410;
define('CIVICRM_GEOCODE_METHOD', 'CRM_Utils_Geocode_ZipTable' );

Attempting to geocode using a zipcode I get the following error (and the changes are not saved);

• warning: Missing argument 2 for CRM_Core_DAO::executeQuery() in /mnt/server/drupal.bachusii/htdocs/modules/civicrm/CRM/Core/DAO.php on line 592.
• warning: Invalid argument supplied for foreach() in /mnt/server/drupal.bachusii/htdocs/modules/civicrm/CRM/Core/DAO.php on line 625.

onherstelbare fout
Sorry, er is een onherstelbare fout opgetreden.

Database foutcode : Unknown column 'MYZIPCODE' in 'where clause', 1054
Terug naar CiviCRM menu.

error
Array
(
[callback] => Array
(
[0] => CRM_Core_Error
[1] => handle
)
[code] => -19
[message] => DB Error: no such field
[mode] => 16
[debug_info] => SELECT latitude, longitude FROM zipcodes WHERE zip = MYZIPCODE [nativecode=1054 ** Unknown column 'MYZIPCODE' in 'where clause']
[type] => DB_Error
[user_info] => SELECT latitude, longitude FROM zipcodes WHERE zip = MYZIPCODE [nativecode=1054 ** Unknown column 'MYZIPCODE' in 'where clause']
[to_string] => [db_error: message="DB Error: no such field" code=-19 mode=callback callback=CRM_Core_Error::handle prefix="" info="SELECT latitude, longitude FROM zipcodes WHERE zip = MYZIPCODE [nativecode=1054 ** Unknown column 'MYZIPCODE' in 'where clause']"]
)

civicrm/CRM/Utils/Geocode/ZipTable.php, 74;
$query = 'SELECT latitude, longitude FROM zipcodes WHERE zip = ' .
CRM_Utils_Type::escape( $postalCode, 'String' );

Changing the line above to read;
$query = 'SELECT latitude, longitude FROM zipcodes WHERE zip = \'' .
CRM_Utils_Type::escape( $postalCode, 'String' ) . '\'';

lessens the error to (The changes are saved now, and geocoding succeeds.):

• warning: Missing argument 2 for CRM_Core_DAO::executeQuery() in /mnt/server/drupal.bachusii/htdocs/modules/civicrm/CRM/Core/DAO.php on line 592.
• warning: Invalid argument supplied for foreach() in /mnt/server/drupal.bachusii/htdocs/modules/civicrm/CRM/Core/DAO.php on line 625.

Line 76 in ZipTable.php calls that function
$dao =& CRM_Core_DAO::executeQuery( $query );
Obviously without the expected second parameter.