Iphone and ipad have duplicate contacts and calendar items

I am using iphone and macbook pro. I have recently purchased ipad and imac and have synchronized all of them. The problem is that my iphone and ipad shows duplicate contacts and calendar items in it. I don't have any ideas why i am getting this problem. Is there anyone who is having some knowledge related with this issue? I am looking to solve this issue as early as possible. Please try to help me out, so that i can come out of this problem. Any suggestion regarding this will be appreciated. Thanks.

I am having iphone, macbook pro, mobileme and a ipad and i am also facing the same problem with my iphone and ipad. I have spent my 10 to 12 hours in searching solution for this problem, but was unable to get it. Can anyone suggest me the fix for this problem? I will be greatly thankful to you if you do this.

I had solved this problem by going through the following steps.

1. First i went to Settings option in my iphone.
2. Then i went to Mail>> Contacts>> Calendars.
3. After going there i selected my mobile me account and turned off my Contacts and Calendars on my macbook sync.
4. Now it will prompt you to save the data locally on your iphone.
5. Once you save it, then the contacts and calendar will not get deleted.
6. After that i turn on the Contacts and Calendars on my system.
7. It will prompt you to merge, so try to select that.
8. After doing all this i was successfully able to get rid of the duplication problem.

Hope it will help to you as well.

I have referred the above reply given by Steyn and also have tried to implement the solution. After trying that i was successfully able to solve my duplication problem. Now when i synchronize my all the devices together, then i am able to get the proper contacts and calendar items on my iphone and ipad. Finally i will thank you for your kind support.

I have tried your solution as i was also getting the same problem. When I am trying to deselecting my Contacts and Calendars from iTunes and MobileMe, then it so not prompting me to save the data. What should i do now from here? I greatly need your help. Please try to show me a direction from here. Also i will like to thank you for your support.

I have also solved my problem after trying that solution given by steyn. It has removed all the duplication from my contacts and calendar. It was really a wonderful solution and i will like to give my thanks to you for providing me your solution. Even others who are facing the same problem can try this solution.