First off, I should point out that the reference quoted is not a mainstream website - many of the opinions expressed on this website are
extremely odd, such as the proposal of a Newtonian background for space-time for example.
Usually we try to limit discussion of physics to mainstream science, however we try and allow a little lattitude as long as this lattitude is not abused to promote or discuss crank theories.
There is a valid point behind some of what the quoted website says which has however apparently been misinterpreted by the original poster, which merits discussion even though the original website quoted doesn't really meet PF standards.
This is the fact that it
may be possible in GR to take "shortcuts" through, for example, wormholes, and arrive at a destination faster than light does, without however ever exceeding the speed of light. The existence of this sort of shortcut has by no means been proven, but it has not been ruled out, either.
The original poster has apparently mistaken the possible existence of these sorts of "shortcuts" for the actual ability to move at a velocity greater than 'c'.
While the speed of light is never exceeded in taking such "shortcuts", there are some possible issues with causality - in popular language, wormholes can become time machines.
The resolution to this issue is not currently known, though Hawking, for instance, has proposed a chronology protection conjecture. It turns out that a wormhole on the verge of becoming a time machine will have a very large flux of virtual particles passing through it. Detailed modelling of what happens is not possible at the current state of knowledge, but it has been suggested that this flux of virtual particles will destroy the wormhole.
For some popular level references on this topic, I'll suggest:
http://www.npl.washington.edu/AV/altvw33.html
at longer length (but not available on the web) there is Kip Thorne's excellent [correction] Black Holes and Time Warps: Einstein's Outrageous Legacy
So if wormholes exist, they may cause problems with causality, even though they would not allow objects to have a velocity larger than that of light.
Wormholes may or may not exist, and if they do exist, mechanisms such as Hawking's chronology protection conjecture may or may not prevent them from becoming time machines.
While serious papers have been written about this issue, see for instance the "Billiard ball paper" http://prola.aps.org/abstract/PRD/v44/i4/p1077_1, the resolution is still very much up in the air.