[asterisk-users] How do I remotely force an *unconfigured* Digium DPMA phone to re-query the network for the DPMA server?

[Alex Villací­s Lasso]

Consider the following scenario:

1) One or more Digium DPMA phones are plugged into the network. I know their IP addresses and MACs.
2) The Asterisk I want to use as the telephony server starts without the DPMA module. Therefore there are no DPMA sessions between the phones and the server.
3) I install DPMA on the server, and write its configuration file for the phones. I will tie each phone to its configuration using the MAC, which I already know (config_auth=mac)
4) I reload the module as required to reload the configuration file.

Now that everything else is ready, I have to make the previously unconfigured Digium phones to query the net for the DPMA server.

How?

I would rather not physically locate and reset every single phone (all 100 of them, to cite a random number). I want a way to remotely force the phones to re-query the net and discover the configured DPMA server. The "digium_phones reconfigure all" would 
work for this, except that it needs an existing DPMA session, and there is none, since I configured the server for the first time. However, since I know the IP addresses of the phones, I could send some kind of notification to the phones. But I do not know 
which one. For some phones other than Digium, some variations of the SIP NOTIFY command will force the phone to request its configuration anew. Is there any equivalent for Digium phones?

A variation: the same Asterisk server has a bunch of configured DPMA phones. I now add a fresh batch of phones to the net. Since their MACs are unknown to the Asterisk server, the phones will remain unconfigured. I add the MACs to the file and reload the 
module. How do I make the fresh batch of phones to re-query the net and pull its configuration without having to physically go to each one and reset or otherwise interact with it?