That only works on the 8100 Pearl which was the original version of the Pearl. The 8110, 8120 and 8130 does not have the changing LED trackball like the 8100 had. So as Lynda said, the only way is to buy a new color trackball. I bought a blue trackball for my 8120 Pearl from Cellular Nationwide Network - 3G, Sony, Panasonic, LG, SonyEricsson, Nokia, Tools, BlackBerry,. Everything you need is there.
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