Gotta run out... so I'm going to assume you have a Flickr account on the phone since that seems to be the main cause for everyone having the problem of the calender causing the awake time.
-If you have enabled syncing with a Flickr account, remove it. The account holds a wake lock in the calendar app and prevents the phone from sleeping. Remove the account and you should have no issues.
Go to Menu > Settings > Account & Sync > Flickr and hit the Remove account button, and then restart the phone.