jQplot treat each item as a new one
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I am using jQplot for a bar graph but I've run into problem.

Here is some sample data:

var s2 = [["28",425, null], ["23",424], ["24",417], ["25",390],["26",393], ["27",392], ["28",369]];

The problem i have is there are two values the same e.g. 28 and jQplot treats this as the same item is there a way to make it treat this as a separate value?