With the plugin CloudBees License Manager enabled, I cannot access my jenkins server.

I upgraded my jenkins install on ubuntu using packages but now I'm getting the following error :

java.lang.NullPointerException
at com.cloudbees.jenkins.plugins.license.BootHook.innerOnLoaded(BootHook.java:59)
at com.cloudbees.jenkins.plugins.license.BootHook.onLoaded(BootHook.java:49)
at jenkins.model.Jenkins.<init>(Jenkins.java:845)
at hudson.model.Hudson.<init>(Hudson.java:81)
at hudson.model.Hudson.<init>(Hudson.java:77)
at hudson.WebAppMain$2.run(WebAppMain.java:214)

If I remove this plugin it works well, except that I cannot see some of my projects as they are in folders.