elysia_cron setup for custom callback
Elysia cron has a hook specifically for that; hook_cronapi():

function hook_cronapi($op, $job = NULL) {
  $items['key'] = array(
    'description' =&gt; 'string',
    'rule' =&gt; 'string',
    'weight' =&gt; 1234,
    'callback' =&gt; 'function_name', 
    'arguments' =&gt; array(...),
    'file' =&gt; 'string', // External file, like hook_menu
    'file path' =&gt; 'string'
  );

  $items['key2'] = ...
  ...
  return $items;
}


Taken from the API.txt file included with the module.