When creating multiple queues and trying to start/stop queue from CLI always first one is started/stopped:
$ ./symfony sfqueue-list-queues frontend
>> feed - stopped, 1 active, 0 completed
>> mail - stopped, 0 active, 0 completed
$ ./symfony sfqueue-start-queue frontend mail
Queue "mail" started.
$ ./symfony sfqueue-list-queues frontend
>> feed - running, 0 active, 1 completed
>> mail - stopped, 0 active, 0 completed
You can even use completely buggy queue name in CLI and first queue will also be started/stopped:
$ ./symfony sfqueue-stop-queue frontend buggyqueuename
Queue "buggyqueuename" stopped.
$ ./symfony sfqueue-list-queues frontend
>> feed - stopped, 0 active, 1 completed
>> mail - stopped, 0 active, 0 completed