MacBook Air (mid 2011) running OS X 10.7.2 won’t stay asleep

I'm running OS X 10.7.2 on a MacBook Air (mid-2011). The computer seems to be waking itself up from sleep. If I go from the black apple in the menu bar and set it to sleep, it wakes up in about 10 seconds. If I let the computer sleep from being idle, then it wakes itself up within four minutes.

Here's what the console output looks like after waking up:

10/13/11 3:07:56.000 PM kernel: Wake reason: EHC2
10/13/11 3:07:56.000 PM kernel: The USB device HubDevice (Port 1 of Hub at 0xfa000000) may have caused a wake by issuing a remote wakeup (2)
10/13/11 3:07:56.000 PM kernel: Previous Sleep Cause: 5
10/13/11 3:07:56.000 PM kernel: The USB device Apple Internal Keyboard / Trackpad (Port 2 of Hub at 0xfa100000) may have caused a wake by issuing a remote wakeup (3)
10/13/11 3:07:56.000 PM kernel: HID tickle 140 ms
10/13/11 3:07:56.000 PM kernel: AppleUSBMultitouchDriver::checkStatus - received Status Packet, Payload 2: device was reinitialized
10/13/11 3:07:57.000 PM kernel: Sound assertion "0 == fAudioEngineArray" failed in AppleHDADriver at line 3047 goto Exit

Does anyone have any suggestions for how to fix this?

The output is more complicated when I have the network on, but I suspect that's unrelated to the actual problem. Here's an example with my ethernet adapter plugged in:

10/13/11 2:33:16.507 PM Console:  Marker - Oct 13, 2011 2:33:16 PM
10/13/11 2:36:54.000 PM kernel: Ethernet [AppleUSBEthernet]: Link down on en2
10/13/11 2:36:54.000 PM kernel: AppleUSBEthernet::disable - Link down, Device eb86000
10/13/11 2:36:55.245 PM configd: setting hostname to "..."
10/13/11 2:36:55.247 PM configd: network configuration changed.
10/13/11 2:36:58.000 PM kernel: Wake reason: EHC2
10/13/11 2:36:58.000 PM kernel: The USB device HubDevice (Port 1 of Hub at 0xfa000000) may have caused a wake by issuing a remote wakeup (2)
10/13/11 2:36:58.000 PM kernel: Previous Sleep Cause: 5
10/13/11 2:36:58.000 PM kernel: The USB device Apple Internal Keyboard / Trackpad (Port 2 of Hub at 0xfa100000) may have caused a wake by issuing a remote wakeup (3)
10/13/11 2:36:58.000 PM kernel: HID tickle 141 ms
10/13/11 2:36:58.000 PM kernel: AppleUSBMultitouchDriver::checkStatus - received Status Packet, Payload 2: device was reinitialized
10/13/11 2:36:58.000 PM kernel: Sound assertion "0 == fAudioEngineArray" failed in AppleHDADriver at line 3047 goto Exit
10/13/11 2:37:01.000 PM kernel: Ethernet [AppleUSBEthernet]: Link up on en2, 100-Megabit, Full-duplex, No flow-control, Port 2, Debug [3100,782d,05e1,41e1,0001,0306]
10/13/11 2:37:02.698 PM ntpd: bind(26) AF_INET6 fe80::2a37:37ff:fe00:e2cd%4#123 flags 0x11 failed: Can't assign requested address
10/13/11 2:37:02.698 PM ntpd: unable to create socket on en2 (23) for fe80::2a37:37ff:fe00:e2cd#123
10/13/11 2:37:02.720 PM rpcsvchost: sandbox_init: com.apple.msrpc.netlogon.sb succeeded
10/13/11 2:37:03.055 PM configd: network configuration changed.
10/13/11 2:37:03.065 PM configd: setting hostname to "..."
10/13/11 2:37:08.070 PM com.apple.launchd: (com.apple.smb.preferences) Throttling respawn: Will start in 5 seconds

Any thoughts would be really appreciated.

Thanks!