cache collection

  $store_id = Mage::app()->getStore()->getId();
  $rootId   = Mage::app()->getStore($store_id)->getRootCategoryId();
  $catCollection  = $_product->getCategoryCollection()->addAttributeToSelect('name')->addUrlRewriteToResult()
                    ->addIsActiveFilter()->addFieldToFilter('path', array('like'=> "1/$rootId/%"))->setOrder('id','ASC');
  $cache          = Mage::app()->getCache();                                  // [TODO] Cache the collection result not sure if this works
  $cache->setLifetime(28800);
  $catCollection->initCache($cache,'customcategoryfilter_', array('collections'));