Soundtrack Secret - "The Last March of the Ents"

We all know and agree that The Last March of the Ents scene from The Lord of the Rings: The Two Towers movie is epic in every sense of the word. Yet there is a secret in the soundtrack, for that is not mere chanting we hear but words in Sindarin, the tongue of the Grey Elves.

Rithannen I geven
Thangen I harn~
Na fennas I daur
Ol dыare ristannen
Eryn echuiannen
I ngelaidh dagrar
Ristar thynd, cъa tawar
Dambedir enyd I ganed
Si linna I waew trin ylf
Iso I dur I chuiyl
I ngelaidh dagrar

Words which, translate to:

Earth shakes, stone breaks, 
The forest is at your door. 
The dark sleep is broken, 
The woods have awoken, 
The trees have gone to war. 
Roots rend, wood bends, 
The Ents have answered the call. 
Through branches now the wind sings. 
Feel the power of living things. 
The trees have gone to war.

However much Peter Jackson botched The Hobbit movies, he did not miss a trick in The Lord of the Rings were it really mattered.