parallelLimit throws RangeError

[skerit]

When I execute my tasks using parallelLimit I get a RangeError: Maximum call stack size exceeded. Here's the code:

Object.each(item[model.modelName], function(value, fieldKey) {

    var field = model.getModelEditorField(fieldKey);

    itemTasks[fieldKey] = function(next_task) {

        field.prepareExport(value, function(err, result) {
            next_task(err, result);
        });
    };

});

async.parallelLimit(itemTasks, 3, function(err, result) {
    next(err, result);
});

When I execute the tasks using the regular .parallel method it works without problems.

[aearly]

is field.prepareExport asynchronous? Does it callback on the same process tick?