Drupal 6 has reached End Of Life (EOL) and is no longer a community supported release. For sites that process payments this is a problem due to the fact that they have to be PCI compliant and the PCI compliance rules require that all software on the site are supported.
Due to this Inguza Technology AB have decided to release a fork of Drupal named Droppe. It is essentially the same piece of software with the difference that it do have both feature improvement and security updates. The Droppe releases will follow the same version numbering as the original Drupal releases did. So the first Droppe fork of Drupal 6 will therefore carry the version number 6.39.
For access to the release send an email to info (at) inguza.com. The code is open source according to the GPL but there is no official download location.