how to reproduce

• go to http://projects.anyware-services.com/explorer/index.html
• select a project
• upload a zip and ask to extract it

Actual behavior

• the user receive an email that contains a link like

  Pour télécharger le document, cliquez sur le lien ci-après ou copiez/collez l'url dans votre navigateur : http://projects.anyware-services.com/explorer/plugins/explorer/resource?id=resources-collection://88856db3-aaab-4034-9ad5-62452f663db3&download=true.

• when you click on it, you get an error :

  ADMINISTRATION - An error occured
  
  java.lang.ClassCastException : org.ametys.plugins.explorer.resources.jcr.JCRResourcesCollection cannot be cast to org.ametys.plugins.explorer.resources.Resource
  Hide details
  org.ametys.plugins.explorer.resources.jcr.JCRResourcesCollection cannot be cast to org.ametys.plugins.explorer.resources.ResourceFailed to process reader<map:read type="ametys-resource"><map:mount>java.lang.ClassCastException: org.ametys.plugins.explorer.resources.jcr.JCRResourcesCollection cannot be cast to org.ametys.plugins.explorer.resources.Resource at org.ametys.plugins.explorer.resources.readers.AmetysResourceReader.setup(AmetysResourceReader.java:96) at org.apache.cocoon.components.pipeline.AbstractProcessingPipeline.setupReader(AbstractProcessingPipeline.java:595) at org.apache.cocoon.components.pipeline.AbstractProcessingPipeline.preparePipeline(AbstractProcessingPipeline.java:499) at org.apache.cocoon.components.pipeline.AbstractProcessingPipeline.process(AbstractProcessingPipeline.java:453) at