Hi,

a few weeks ago we configured jboss.org JIRA instance (issues.jboss.org) to allow remote linking of issues with Hibernate JIRA (hibernate.onjira.com) and Apache JIRA (issues.apache.org/jira). This feature allows better linking of issues with upstream/downstream project issues. Linking with Hibernate JIRA is bidirectional, so you can link from Hibernate JIRA issues to jboss.org issues too. Linking with Apache jira is possible from jboss.org JIRA only,  linking is not configured on Apache jira side.

The feature is available from common jira issue Link action. Linking dialog now contains new field called "Server", where you can specify JIRA server you want to link issue from. Then you can directly type in issue key from selected server, or search issue against the server.

Details about JIRA remote issue linking are available in JIRA documentation.