Try changing the :empno to just empno in bind* it is not expected or needed:

$command = $connection->prepare('SELECT EMP_NO FROM EMPLOYEE WHERE EMP_NO = :empno');
$command->bindParam('empno', $value, PDO::PARAM_STR); // does not work
$command->bindValue('empno', $value, PDO::PARAM_STR); // does not work

This bug has been fixed in SVN.

Snapshots of the sources are packaged every three hours; this change
will be in the next snapshot. You can grab the snapshot at
http://snaps.php.net/.

 For Windows:

http://windows.php.net/snapshots/
 
Thank you for the report, and for helping us make PHP better.

tested and result was 2


cat test.php 
<?php
$connection = new 
PDO('firebird:dbname=localhost:/var/lib/firebird/2.5/data/employee.fdb', 
'SYSDBA', 'masterkey');

$value = '2';

$command = $connection->prepare('SELECT EMP_NO FROM EMPLOYEE WHERE EMP_NO = 
:empno');
$command->bindParam(':empno', $value, PDO::PARAM_STR); // does not work
$command->bindValue(':empno', $value, PDO::PARAM_STR); // does not work

#$command = $connection->prepare('SELECT EMP_NO FROM EMPLOYEE WHERE EMP_NO = 
?');
#$command->bindParam('1', $value, PDO::PARAM_STR); // works
//$command->bindValue('1', $value, PDO::PARAM_STR); // works

$command->execute();
$dataset = $command->fetchAll();
foreach($dataset as $record)
  echo $record[0] . "<br />";
?>

FYI. This issue exists in 5.3.6 as well.


PHP 5.3.6 with Suhosin-Patch (cli) (built: Sep  8 2011 19:34:00) 
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