In drupal, is there a field type with variable number of values?

Using cck I've created a new content type, Contact. A contact can开发者_JAVA百科 have 1 or more phonenumbers.

Is possible to create a field type (string, number or node reference) so that the user creating content can add more phonenumbers to a contact?

You can set a "number of values" for a CCK field, just set it to unlimited. It's in "Manage Fields" under "Global settings".