Magento - cron syntax for helper function

Everywhere I look I see the syntax for cron jobs in magento about as follows:

<crontab&开发者_Go百科gt;  
    <jobs>  
        <cron_name>
            <run><model>some_module/some_model::some_function</model></run>
        </cron_name>
    </jobs>
</crontab>

Is there however also a syntax for executing functions of for example helper classes? It seems so overkill to make a model just for some small cron task. Or should it always be a model function?

Technically I don't think you should have a Helper without a corresponding Model.

I would take your own advice and just create a simple Model to call your helper functions. If not I think you would need to do some reworking of the Varien/Core Cron functionality. Doesn't sound like it would be worth the trouble to me.