The most easy way to solve your problem is to add two buttons, the first should be regular button and the second is submit by e-mail one. Set the
'presence' property of the second to 'hidden' and add to it your email address. To the first button on 'click' event add the script like this
var answer = xfa.host.messageBox("Send e-mail?","e-mail",2,1);
Hope this helps.