Help Events created on Android don't sync with Microsoft Exchange account

[ToonFan]

I have a really frustrating problem when syncing the calendar on my Desire S with Exchange Active Sync. Contacts and Emails are fine and sync both ways. However although appointments created on my iPad or Outlook sync down to my Android, any appointment created on my Android doesn't sync the other way. I can delete appointments created on another devices using my phone and that does sync i.e. deletes it off the other devices, however editing an appointment on the Android doesn't sync the change. I've tried deleting the account, deleting all data from the calendar and recreating the account but that doesn't work. this is so annoying as I've double booked a couple of meetings because they were in my phone but not on my laptop.