Custom BB code
 

I can't quite figure this out. I got the BB code to work for youtube but I need one for charts.

Here it is

http://stockcharts.com/c-sc/sc?s=EESO&p=D&b=5&g=0&i=t94046363185&r=9115


When you change the letters in bold it changes the chart.


So I want it to look like this:

[chart]eeso[/chart]


and then the chart pops up.


How do i do this correctly?


Thanks.