i try to change the mail subject you get by an invitation mail from alfresco share. So i have modified the file invitation-nominated_processdefinition.xml but there is no change in behavior. I know that the mail text is written in invite-email.ftl but there is no place to change the mail subject.
Are you sure the process_definition.xml has been redeployed when you restarted Alfresco ? See workflows-context.xml, and property "redeploy", to check this fact.
sorry I was wrong, see file bootstrap-context.xml, or maybe remote-api-context.xml. It seems that I don't have the same version of Alfresco as you have.