Getting Quartz.net to ignore misfires

Question

I'm building a windows service which is performing a scheduled task which processes a queue of commands (from a legacy system) at a regular interval (once per min) using Quartz.net

If the task takes longer than 1 min, which would be unusual but possible under certain circumstances, I'd like it to simple ignore the triggers it missed firing.

However I can't seem to get this to happen. It does the processing and then quickly fires all the triggers it missed in quick succession. As I understand you can set a threshold for the misfires but I don't seem to be-able to get this working.

I'm using [DisallowConcurrentExecution()] on the Job to ensure only one instance of the job is running at any one time.

Below are a couple of snippets. First passing in some config info - is this how you set the misfire threshold?

    NameValueCollection config = new NameValueCollection();
    config.Add("quartz.jobStore.misfireThreshold", "600000");

    schedFact = new StdSchedulerFactory(config);

Building a trigger with what I assume to be the correct setting of Ignore misfires:

    var trigger = TriggerBuilder.Create()
                    .WithIdentity("trigger1", "group1")
                    .StartNow()
                    .WithSimpleSchedule(   x => x.WithMisfireHandlingInstructionIgnoreMisfires()
                    .WithIntervalInSeconds(60)
                    .RepeatForever())
                    .Build();

Thoughts much appreciated.

Code for the Job: Just playing with rough ideas at this point so just running in a console app and randomly delaying a job so it shoots over the interval which is just set at 10 seconds for this. All the backed up misfires fire in quick succession after a couple of delays.

[DisallowConcurrentExecution()]
public class SomeJob : IJob
{
    public SomeJob() { }
    public void Execute(IJobExecutionContext context)
    {
        Random rnd = new Random(DateTime.UtcNow.Second);
        int delay = rnd.Next(2);
        Console.WriteLine("Executing Job with delay of "+ delay + "  at " + DateTime.UtcNow.ToString());

        if (delay == 1)
        {
            System.Threading.Thread.Sleep(1000 * 25); // sleep for 25 seconds
        }
    }
}





Example console output:
Executing Job with delay of 1  at 21/05/2015 21:27:17
Executing Job with delay of 1  at 21/05/2015 21:27:42
Executing Job with delay of 0  at 21/05/2015 21:28:07 <-- stacked misfires
Executing Job with delay of 0  at 21/05/2015 21:28:07 <--
Executing Job with delay of 0  at 21/05/2015 21:28:07 <--
Executing Job with delay of 0  at 21/05/2015 21:28:07 <--
Executing Job with delay of 0  at 21/05/2015 21:28:16
Executing Job with delay of 0  at 21/05/2015 21:28:26
Executing Job with delay of 1  at 21/05/2015 21:28:36
Executing Job with delay of 0  at 21/05/2015 21:29:01
Executing Job with delay of 0  at 21/05/2015 21:29:01
Executing Job with delay of 1  at 21/05/2015 21:29:06