"Lately" (like in the last few months), I'm unable to start the Clockwork Mod recovery image on my Nexus S with Oxygen 2.2.1. When I select "boot to recovery mode" (or want to start a ROM backup) in ROM Manager Premium, it reboots and I see the Android icon. The very first line is red and reads:
FASTBOOT MODE - NO BOOT OR RECOVERY IMG
I've (supposedly…) reinstalled the recovery image multiple times and ROM Manager tells me, that I'm on the latest version already (188.8.131.52).
How do I install the Clockwork Mod recovery image? My phone is rooted, if that's important.