Not solving your problem directly but...
This scripted Bow example may be of use to you:
PHP Code:
//#CLIENTSIDE
function onWeaponfired() {
freezeplayer(0.1);
setani("shoot", "wbow1.png");
setshootparams("classic", "arrow", player.dir, player.account);
temp.angl = getangle(vecx(player.dir), vecy(player.dir));
shoot(player.x + 0.5 + vecx(player.dir), player.y + vecy(player.dir), player.z, temp.angl, 0, 0, "classic_arrow", player.dir);
}
The additional parameters in setani are well.. parameters in the gani:
setani(ani, param1, [param2, param3, ...]);