JSON Object Not Parsing In Firefox

The JSON object I am using is as below . this object is returned after an AJAX call

{"application" :[
{optionValue:"101", optionDisplay: "estmt"},
{optionValue:"11", optionDisplay: "Arif"},
{optionValue:"12", optionDisplay: "JC"}
]}

In the JS i am using the below code

data = ajaxRequest.responseText ;
var jsonOBJ = eval('(' + data + ')');
len = jsonOBJ.application.length ;
key = jsonOBJ.application[i].optionValue ;
value = jsonOBJ.application[i].optionDisplay ;

Internet Explorer is able to process the above code , but while trying
from Firefox , I am getting the below error message

jsonOBJ has no properties
[Break on this error] len = jsonOBJ.application.length ;