gistfile1.php

<?php
class Enterprise_CustomerSegment_Model_Observer
{
    
    public function addSegmentsToSalesRuleCombine(Varien_Event_Observer $observer)
    {
        if (!Mage::helper('enterprise_customersegment')->isEnabled()) {
            return;
        }

        $additional = $observer->getEvent()->getAdditional();
        $additional->setConditions(array(array(
            'label' => Mage::helper('enterprise_customersegment')->__('Customer Segment'),
            'value' => 'enterprise_customersegment/segment_condition_segment'
        )));
    }
    
}