BlackBerry:

NOTE: This article does not apply to sites running NLES v4.5.0. The behavior for synchronizing Reminder Notes has been changed such that Reminder Notes will remain as Reminder Notes regardless of what has been changed on the device.

Problem:
I am getting reminder notes on my device and even though I am not making any changes to them, on the day of the event they are going back to the server as an All Day Event.

Solution:
If you have the default reminders on the device turned on for the calendar, the reminder will pop up for the note and then you dismiss that reminder, Notify considers that a change.  It will then send it back to the server as an All Day Event. The way to prevent this from happening is to turn OFF the default reminder in the BlackBerry calendar. To turn off the default reminders go into the Calendar -> click on the wheel -> select options -> set the default reminder to NONE.