A number of JIRA customers have been asking about the status of full LDAP support in JIRA. This page provides an overview of the current situation.
We intend to integrate JIRA with LDAP, however the task is quite an undertaking, and requires significant changes to JIRA internals in order to ensure the integration works correctly and smoothly.
Atlassian has taken some serious steps in making this feature available by building a framework called 'Atlassian User', which allows Atlassian products to work with LDAP. We have recently integrated Atlassian User with Confluence, a product with a slightly smaller code-base than JIRA, so that we can learn from the experience.
Integrating Confluence with Atlassian User (and hence LDAP) turned out to be a very complex process, which uncovered a number of issues. At present, Confluence-LDAP integration and configuration is the number 1 issue for Confluence Support. Currently, we are working on ironning out the problems that Confluence is facing with LDAP integration, and fixing Atlassian User bugs that we find. After that we will be looking at migrating JIRA to Atlassian User.
As you might be aware, Atlassian also has a product called Crowd, an identity management and SSO system, which helps to integrate JIRA (and other web applications) with LDAP. However, launching Crowd does not mean that we are not planning to deliver JIRA-LDAP integration.