[Inf-IT DAVcl] Creating a new event by duplication...

Hello, first of all thanks for all the work done by the Caldavzap and Davical developers! Working with caldavzap v.0.13.1 (on davical v.1.1.5) I noticed that if I create a new event duplicating a previous one, the previous still appears in caldavzap interface, but it disappears on other clients like Lightning (thunderbird add-on) or Apple iCal. Accessing the davical database entries regarding the two events, it appears that both have been stored but strangely they have the same UID. Is it a bug? Does it regard Caldavzap or Davical? Thanks for your kind cooperation and help Best regards Dario