Different times for Sprite frames

I am using a sprite sheet of 2 frames.

the code is:

sprite.add( spriteSet3, “frog”, 1, 2, 500, -1 )

which means each frame is shown for 500 milli seconds.

But i want the first frame to display for 500 milli seconds, and second to display for 2000 milli seconds. how can i do that?

thanks. [import]uid: 175611 topic_id: 30594 reply_id: 330594[/import]