Don't know how to import task properties of type

I have a type 1 task plugin that works fine if used with the UI adding the task, but when used inside java bamboo-specs, stored inside a repository it fails.

I have had a lot of other failures along the way, but now I’m really stuck.

The thing is that everything works fine until it tries to load the tasks bamboo-specs implementation of TaskProperties.

I have found out that it can’t find the plugin by key. I have checked this key that the log states that it’s searching for and it is correct as a understand it, if I compare it to the installed plugins key in the Manage Apps view in Bamboo.

Key configuration in atlassian-plugin.xml:

<taskType key="releasenotestask" name="Release Notes Task"
class="com.mmm.bamboo.plugins.releasenotes.ReleaseNotesTask">

The TaskProperties class returns the same information in getAtlassianPlugin():

private static final AtlassianModuleProperties ATLASSIAN_PLUGIN = new AtlassianModuleProperties(
"com.mmm.bamboo.plugins.releasenotes:releasenotestask");

@NotNull
@Override
public AtlassianModuleProperties getAtlassianPlugin() {
return ATLASSIAN_PLUGIN;
}

The bamboo log show the following:

[TaskDefinitionExportHelper] Plugin com.mmm.bamboo.plugins.releasenotes:releasenotestask not installed or disabled. Falling back on generic export.
[RepositoryStoredSpecsServiceImpl]
java.lang.IllegalStateException: Don't know how to import task properties of type: com.atlassian.bamboo.specs.model.task.ReleaseNotesTaskProperties

Before this I stopped on that the YamlHelper did not allow that the TaskProperties was in another package than com.atlassian.bamboo.specs.model.task.

Any suggestions?