Ajax Register - Date Field problem

On cozinhanet.sitesw8digital.com.br/cadastro-pessoa-fisica I have set a date field (Data de Nascimento) and when a set a date like "16/07/1975" it pass on ajax validation but I got a severe page 500 error:
"Erro: 500
DateTime::__construct(): Failed to parse time string (16/07/1975) at position 0 (1): Unexpected character"

Whats happen?

You can't have date in format DD/MM/YYYY
It has to be in MM/DD/YYYY

It can't make that way.
On my country this date format (MM/DD/YYYY) is confused, and on plugin setting I have a option to set DD/MM/YYYY.
I atach the screen of this option...

That option is DD-MM-YYYY, so you can't enter it like DD/MM/YYYY
Enter it as 16-07-1975 and it will work.

Fun... and you can make a option for DD/MM/YYYY beyond dd-mm-yyyy or mm-dd-yyyy in plugin settings??

...you can make a option for DD/MM/YYYY beyond dd-mm-yyyy or mm-dd-yyyy in plugin settings??

or give me instructions to do so?