PowerStore uses Spry validation (built into Dreamweaver CS3 and CS4) for its client-side validation set to trigger "onBlur" (when you tab from field to field). The older Validation Toolkit uses a proprietary system which does not allow CSS-controlled state changes like Spry does. However, we are working on the next generation version of Validation Toolkit which will use Spry validation, as well as PHP server-side validation.
Best - Joe