Customer Email with diacritics isn't allowed

[Drakhunter]

Magento2 doesn't allow E-Mails with diacritics in CURL Requests.
According to wikipedia this should be allowed, but Magento is restricting it.

Is there a Fix or Workaround or something?

Preconditions

1. Magento Version 2.1.8

Steps to reproduce

1. get email address with diacritics (pepé@emailtest.com)
2. create json data object with email
   $data = [ 'customer' => [ 'email' => pepé@emailtest.com ] ]
3. create user using curl via /index.php/rest/V1/customers

Expected result

1. User should be created with correct email address

Actual result

1. {"message":"\"Email\" ist keine g\u00fcltige E-Mail-Adresse." (roughly translated: Email isn't a valid E-Mail-Address)

Additional Notes

Reproduced it via Swagger with using the following query /swagger#/customerAccountManagementV1/customerAccountManagementV1CreateAccountPost

The response is :

{
  "message": "\"Email\" is not a valid email address."
}

But this is also reproducible if try to create a customer from Magento Admin

[magento-engcom-team]

@Drakhunter, thank you for your report.
We've created internal ticket(s) MAGETWO-83378 to track progress on the issue.

[rparsi-boxycharm]

@magento-engcom-team any updates? We need a fix asap