JIRA 6.4 - Plugins can not depend on JIRA Agile packages anymore

Our plugin (Plangle, https://marketplace.atlassian.com/plugins/com.moresimp.plangle), depends heavily on JIRA Agile.

After upgrading JIRA to 6.4 our plugin stopped working because an OSGI dependency error:
[INFO] [talledLocalContainer] 2015-03-23 09:59:37,280 localhost-startStop-1 ERROR[plugin.osgi.factory.OsgiPlugin] Detected an error (BundleException) enabling the plugin 'com.moresimp.plangle' : Unresolved constraint in bundle com.moresimp.plangle [155]: Unable to resolve 155.0: missing requirement [155.0]package; (package=com.atlassian.greenhopper.api.rank). This error usually occurs when your plugin imports a package from another bundle with a specific version constraint and either the bundle providing that package doesn't meet those version constraints, or there is no bundle available that provides the specified package. For more details on how to fix this, see https://developer.atlassian.com/x/mQAN

Which obviously means that the container can not satisfy our dependency to 'com.atlassian.greenhopper.api.rank'...

We checked the mentioned page but could not find out what went wrong in JIRA 6.4, since this worked before the upgrade with the same JIRA Agile version.
our code snippet that imports rank service...

<component-import key="rankService" interface="com.atlassian.greenhopper.api.rank.RankService" filter=""/>

Additional information... our plugin fails to start only when JIRA starts up.
It works if we re-install the plugin on a running JIRA instance.

After some investigation it seems that in JIRA 6.4, JIRA Agile is ALWAYS the last plugin that is loaded by Felix, no matter what dependency we specify...

*It also happens with other plugins that depend on JIRA Agile like
https://marketplace.atlassian.com/plugins/net.brokenbuild.agile-reports*

Now we are blocked with our plugin development because of this error.