So my 2009 iMac won't sleep under Mountain Lion. Have tried the usual advice on Apple's site regarding resetting PRAM etc. I have copied what appears in Console when I try to get it to sleep. Wondering if anyone had any ideas...
29/08/2012 14:06:59.067 com.apple.backupd-helper[2856]: Not starting Time Machine backup after wake - less than 60 minutes since last backup completed.
29/08/2012 14:07:00.121 WindowServer[87]: Created shield window 0x52 for display 0x04272580
29/08/2012 14:07:00.129 WindowServer[87]: device_generate_desktop_screenshot: authw 0x0(0), shield 0x0(0)
29/08/2012 14:07:00.142 WindowServer[87]: device_generate_lock_screen_screenshot: authw 0x0(0), shield 0x0(0)
29/08/2012 14:07:00.154 WindowServer[87]: handle_will_sleep_auth_and_shield_windows: no lock state data