zentao/extension/ipd/task/ext/lang/en/ipd.php

<?php
$lang->task->confirmDemandRetract = 'Confirm Retract';
$lang->task->confirmDemandUnlink  = 'Confirm';

$lang->task->disabledTip = new stdClass();
$lang->task->disabledTip->startTip          = 'The current phase cannot start the task until the previous phase is closed!';
$lang->task->disabledTip->finishTip         = 'The current phase cannot finish the task until the previous phase is closed!';
$lang->task->disabledTip->recordWorkhourTip = 'The current phase cannot record the task until the previous phase is closed!';