It seems that since recently the seam init (starting at Welcome to Seam 1.1.5.NX in the logs) occurs before all nuxeo jars are deployed wich make it failed to register the nuxeo audit client beans as seam components though they are successfully registered as EJB3 afterwards.
The history tab is thus broken as some customer projects with Seam components (though not all customer project are affected for some unexpected reason... ).