Sprite Animator (walker boys)- Jumping

Hello everyone

Right now im using This animation script for 2D sprites

I understand basic of how this script works, but i want to modify it because if i want to play jump animation it never starts from the first frame of my sprite because it want to continue from where it stops, this is no problem when walking or running but if I want to play Jump animation it cant start in the middle ...

Can someone point me to right direction? Where to look, to know how to edit it? or some complex way to play jump animation ? thanks

Code: // Animation Sprite Sheet

 // Walker Boys (www.walkerboystudio.com)
 // March 18, 2011
 // Description: Plays an animated sprite using a sprite sheet
 // Instruction: Assign script to a gameObject with a material/texture (sprite sheet) 
 // Function arguments: 
 // columnSize      - number of frames across (horizontal)
 // rowSize         - number of frames down (vertical)
 // colFrameStart   - where frame starts (remember 0 is first number in counting)
 // rowFrameStart   - where frame starts (remember 0 is first number in counting)
 // totalFrames     - number of frames in the animation (count regular)
 // framesPerSecond - how fast do you want it to play through (Standard: 12 - 30 fps)
 
 function aniSprite (columnSize, rowSize, colFrameStart, rowFrameStart, totalFrames, framesPerSecond)// function for animating sprites
 {
     var index : int = Time.time * framesPerSecond;                                                    // time control fps
     index = index % totalFrames;                                                                    // modulate to total number of frames
     
     var size = Vector2 ( 1.0 / columnSize, 1.0 / rowSize);                                            // scale for column and row size
     
     var u = index % columnSize;                                                                        // u gets current x coordinate from column size
     var v = index / columnSize;                                                                        // v gets current y coordinate by dividing by column size
 
     var offset = Vector2 ((u + colFrameStart) * size.x,(1.0 - size.y) - (v + rowFrameStart) * size.y); // offset equals column and row
     
     renderer.material.mainTextureOffset = offset;                                                    // texture offset for diffuse map
     renderer.material.mainTextureScale  = size;                                                        // texture scale  for diffuse map
 
     //renderer.material.SetTextureOffset ("_BumpMap", offset);                                        // texture offset for bump (normal map)
     //renderer.material.SetTextureScale  ("_BumpMap", size);                                        // texture scale  for bump (normal map) 
 }