Highlight a particular bar with different color - Extjs 4 Column Chart

I've a requirement to highlight a single bar { out of many } in different stroke and color, I tried to alter the highlightCfg basing on my condition as

if(storeItem.get(nameColms) == 'Others')

{

highlightCfg = {

"stroke-width": 10,

stroke: '#333'

};

}

else

highlightCfg = {

"stroke-width": 3,

stroke: '#000000'

};

and assigned this highlightCfg variable for the highlight config. But it didn't work :((

Please post some suggestions, thanks in advance.

-

Satya Dileep Kumar