Limited to two tones or frequencies max?

I’ve recently run accross an issue with setting up our Asterisk server in regards to certain notes I need to implement.

I can’t seem to pecify more than two frequencies in the zonedata.c file or in the indications.conf file. For example a custom tone, 1400+2060+2450+2600 for receiver off-hook tone.

Even those small Linksys VoIP adapters the PAP2s are able to play up to 4 or 5 tones, at varying amplitudes.

Anyways, because of this limitation, it’s impossible to implement this or any other tones that I want which are comprised of four different frequencies.

I looked around and found the tonezone.c file which contains the source code for (I’m assuming) processing the frequencies you specify. I noticed that there is only freq1 and freq2 specified in the code.

I’m not an expert at C+ but I’m going to try and add freq3 and freq4 as well to all the places I find freq1 and freq2. I also have to edit the zaptel.h file since it’s included in tonezone.c’s programming.

Is this a proper way of adding the ability for more than two frequencies? Are there any other options I can use? It just seems like such a pity that such a powerful system would have a limitation like this.

Thanks everyone, cheers.