Don't use the $.getJSON method as it, as you are finding out, has no
way to handle an error...
use the generic $.ajax instead
var Params = {};
Params.type = "GET";
Params.url = "qtool";
Params.processData = true;
Params.data = {action: "executeQuery", entity_name: queryText };
Params.dataType = "json";
Params.success = function(data) {
alert(data);
};
Params.error = function(x,y,z) {
alert(x.responseText);
};
$.ajax(Params);
that way "x" will be the error response from the server (which
apparently you are running into)
