why use org.apache.geronimo.specs:geronimo-jpa_3.0_spec:1.1.1 in G 2.1.5 branch?

[Forrest Xia]

Hi,

When I build G 2.1.5 branch, I found a dependency

<dependency>
                <groupId>org.apache.geronimo.specs</groupId>
                <artifactId>geronimo-jpa_3.0_spec</artifactId>
                <version>1.1.1</version>
</dependency>

jpa 3.0 confused me. However, I found there is a spec
"geronimo-jpa_1.0_spec" released, why not using it?

Thanks for comments!

Forrest