Email validation not working correctly

1

Can anyone tell me why it it throws and error and doesn’t validate when the user uses an cap letter in the email? Thanks for all your help!

code:
public function validateEmail(form_email_value:TextField):Boolean
{
var email_exp:RegExp = /^[a-z0-9][-._a-z0-9]@(([a-z0-9][-_a-z0-9].)+[a-z]{2,6}|((25[0-5]|2[0-4]\d|[01]?\d\d?).){3}(25[0-5]|2[0-4]\d|[01]?\d\d?))$/x;
if( form_email_value.text == ‘’ )
{
form_email_value.text = ‘Email is required.’;
return false;
}
if( !email_exp.test(form_email_value.text) )
{
form_email_value.text = ‘Email is invalid.’;
return false;
}
return true;
}