Estonian ID code field

This module provides an Estonian Personal identification code (isikukood) field
type. More details http://en.wikipedia.org/wiki/National_identification_number#Estonia

The code form is GYYMMDDSSSC, where G shows sex and century of birth (odd number male, even number female, 1-2 19th century, 3-4 20th century, 5-6 21st century), SSS is a serial number separating persons born on the same date and C a checksum.

This module has code checksum validation. Also there are two widgets and displaying
formatters:

• Plain, this is just the code without any whitespace or delimiters, the usual
  way of representing the code
• Formatted, the code is broken into segments: G YY MM DD SSS C

Because there are privacy issues concerning ID codes, there are also permissions
to view and edit codes.

The permissions need testing with different entities like commerce, right now it relies on the entity having an "uid" field.

GitHub

This is also up on GitHub: https://github.com/koosh/Estonian-ID-code-field-for-Drupal-7. Feel free to fork it ;)