With a little bit of coding/hacking it can be done. Edit FOP2Callbacks.pm and add the following inside the flashcommand if else block:

    } elsif($command eq "playdtmf") {
       $contexto = $parameters[2];
       my $mychannel = main::get_btn_config( "$contexto", $parameters[0], 'MAINCHANNEL');
       my $myactive = main::get_active_link($mychannel);

       $return  = "Action: PlayDTMF\r\n";
       $return .= "Channel: $myactive\r\n";
       $return .= "Digit: ".$parameters[1]."\r\n";
       $return .= "\r\n";
       push @allreturn, $return;

       return @allreturn;
    }

That will receive dtmf entered via the dialbox dialpad and inject them to the linked channel. I will probably add this to the main event handling on the next release.

Best regards,