If one follows the link to the stable version at
http://jackrabbit.apache.org/jcr/jackrabbit-roadmap.html there is a
confusion of 2.18.0-SNAPSHOT and 2.18.0.
https://svn.apache.org/repos/asf/jackrabbit/branches/2.18/ has a
pom.xml at
https://svn.apache.org/repos/asf/jackrabbit/branches/2.18/pom.xml with a
parent reference:
<parent>
<groupId>org.apache.jackrabbit</groupId>
<artifactId>jackrabbit-parent</artifactId>
<version>2.18.1-SNAPSHOT</version>
<relativePath>jackrabbit-parent/pom.xml</relativePath>
</parent>
The parent at
https://svn.apache.org/repos/asf/jackrabbit/branches/2.18/jackrabbit-parent/pom.xml
matches the snapshot in the version
<groupId>org.apache.jackrabbit</groupId>
<artifactId>jackrabbit-parent</artifactId>
<name>Jackrabbit Parent POM</name>
<version>2.18.1-SNAPSHOT</version>
<packaging>pom</packaging>
The download link for the zip of the project sources does give the
production 2.18.0 sources.
This seems odd but I am not an active developer of the project (just an
active user).
Ron