Date Popup not working

Date Popup module is not working for me.

I enabled the following modules in the order shown:

1) CCK content module

2) Date API
2) Date Timezone
2) Date
2) Date Php4

Then I added the following form element:

   $form['test'] = array(
            '#type' => 'date_select',
            '#title' => t('Date'), 
            '#date_format' => 'm/d/Y', 
            '#date_year_range' => '-3:+3',
            '#description' => "Please enter release date.", 
            '#tree' => TRUE,
        );

This worked, in that I got a drop-down selection for year, month and date.

Then I enabled Date Popup module.

At that point the date field stopped showing up on browser.

I then disabled Date Popup and the date field still didn't show up. I disabled, and even uninstalled all Date modules, reinstalled and re-enabled them except for Dare Popup, but nothing. The drop-down selection doesn't show up anymore.

I'm running cck-6.x-2.2 and date-6.x-2.1.