"clebert.suconic(a)jboss.com" wrote : The date portion is only used to start the counter. | After the server is started, the counter is added as any other longer. And I don't think any server in the workd would be able to overlap a long counter. | That's not the problem I was referring to. If the server is started after 398 days, there is a possibility it is started with the same time component as when it was started before 398 days, the counter would be zero, so there might be overlaps. This is nothing to do with wrapping the long counter. That's why I suggested you not taking the 10 or so least significant bits from the time, since that would avoid the problem. The negative increment loop also appears flawed. Let's discuss this on IRC. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4179219#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...