Please specify what do you mean under you statement "I could not enter the site".
If you could not enter your site for over 5 hours then you should look at your hosting or other places to find the reason why your site was unreachable.
The callback is sent when you are entering Dolphin Administration panel and it times out in 1 minute or so. The callback does not influence on the whole site operation in anyway from the user side.
As for your concerns, Sammie has see more reported about the problem providing the arguments from the webmaster point of view. As the whole licensing system is supposed to change in D7, but the callback system was supposed to be the same. So, Sammie's arguments have forced us to re-consider callback system in order not to bring up any inconveniences with it.
Please specify what do you mean under you statement "I could not enter the site".
If you could not enter your site for over 5 hours then you should look at your hosting or other places to find the reason why your site was unreachable.
The callback is sent when you are entering Dolphin Administration panel and it times out in 1 minute or so. The callback does not influence on the whole site operation in anyway from the user side.
As for your concerns, Sammie has see more