Here is an article that goes in to the detail[0]. In so many words, you can use the superluminal telephone to transmit information to your own past. In essence, there is a certain amount of freedom in the simultaneity of events that is well-known to exist (having been experimentally verified). You can abuse it to create time paradoxes if and only if you can send messages faster than light - without FTL it is a curiosity that seems strange to some but otherwise doesn't upset anything.

[0] http://www.theculture.org/rich/sharpblue/archives/000089.htm...