[xXziroXx]

For example.

1) replaceani("walk", "graalaxy_harpoon_walk");
That replaces the WALKING ani with graalaxy_harpoon_walk.
2) replaceani("graalaxy_harpoon_walk", "graalaxy_harpoon_empty_walk");
That tries to replace a DEFAULT ani named graalaxy_harpoon_walk, which obviously doesn't exist.
3) replaceani("walk", "graalaxy_harpoon_empty_walk");
That does the trick! And to replace the harpoon walk ani to the default walk ani...
4) replaceani(walk", "walk");