Switch – Gigabit ports on Dell Powerconnect 2324 never worked

I have a Dell Powerconnect 2324 with Gigabit ports – 24 ports 10/100 ports with 2 Gigabit ports – that never worked. It's supposed to auto-detect everything, but even trying different combinations I never get any lights or connection on the 2 Gigabit ports. I've always wired my uplink into the normal 10/100 ports (which always works, whatever the configuration of cables). I've seen this problem reported by a couple of other people on the Internet with no solution. Am I missing something obvious?

UPDATE

For some reason the manual doesn't seem to be linked from that page. I only have one other port connected, and I've tried it in several. The Gigabit ports are 10/100 compatible and I would think auto-sensing (not stated explicitly, but says all ports are MDI/MDIX sensing and auto-speed/duplex). If not auto-sensing, then there is no information about how to configure the switch (it is unmanaged).