try changing:
var sprytextfield5 = new Spry.Widget.ValidationTextField("sprytextfield5", "phone_number", {validateOn:["blur"]});
var sprytextfield6 = new Spry.Widget.ValidationTextField("sprytextfield6", "mobile_number", {validateOn:["blur"]});
to:
var sprytextfield5 = new Spry.Widget.ValidationTextField("sprytextfield5", "phone_number", {validateOn:["blur"], useCharacterMasking:true});
var sprytextfield6 = new Spry.Widget.ValidationTextField("sprytextfield6", "phone_number", {validateOn:["blur"], useCharacterMasking:true});