You can download Sun Java System Directory Server Enterprise Edition 6.1 software from the following location.
http://www.sun.com/software/products/directory_srvr_ee/get.jsp
The download page serves as a starting point to direct you to the proper downloads depending on the distribution type you need to download. Directory Server Enterprise Edition 6.1 is available in the following distributions.
Native package distribution
zip distribution
For a comparison of the two distributions, see Directory Server Enterprise Edition Software Distributions in Sun Java System Directory Server Enterprise Edition 6.1 Installation Guide.
Directory Server Enterprise Edition 6.1 is available in the following forms.
Native patch — patch to upgrade Directory Server Enterprise Edition 6.0 native packages installation.
There is no Native patch delivery for Windows in Directory Server Enterprise Edition 6.1.
Zip based distribution — standalone delivery to install Directory Server Enterprise Edition 6.1 or upgrade Directory Server Enterprise Edition 6.0 zip installation.
For information on patch numbers, see Directory Server Enterprise Edition 6.1 Installation Instructions in Sun Java System Directory Server Enterprise Edition 6.1 Installation Guide.