Well, there isn't much to do, for anyone that cares just
File -> Open -> find your pattern image
Save as as gimp pattern, fill the GIMP Description with the pattern's name and well save it,
place it on your .gimp-2.4 pattern folder.
works like a charm! I'm collecting some patterns to release all at once, preferably under CC .. hope i find them all so i can release a package here ^^