Hi. In my job we are developing some new features to OTRS, one of them is the capability to close a ticket only when the childrens (and i mean all the referenced or linked childrens) have been closed succesfully, according to some rules configured by the admin. I know that with the ACL's i can avoid the closing of tickets, but only based on ticket attributes. The other way i'm evaluating is to build a module that responses to the event "TicketStateUpdate" and, if the ticket is suposed to not be closed according to the rules mentioned above, the module would "undo" the close event. What i want to know if its possible to use the ACL's to do this (this is, use the ACL's based not in a ticket attribute, but based in a method), something like this: $Self->{TicketAcl}->{'ACL-Name-1'} = { # match properties Properties => { # current ticket match properties Ticket => { Kernel::Modules::SomeMethodThatVerifyRules(); } }, ..... I have other question, about the EventHandler. Does it responds to the event after or before that the event has been done??? Thank you very much.