created ringtone in iTunes 10, won't transfer to iPhone

Hello all. I have successfully created a ringtone in itunes 10 on my macbook pro, and converted it to the m4r format. The length is about 20 seconds long. I have even tried it at 6 seconds long. When I sync to my iphone 4s it gives me an error code that says that "this phone can not play this" I have also gotten the error "this phone can't transfer because the duration is too long." The only item I have checked off is the ringtone that I created. I have also tried to do the same thing on my windows based computer, but was unsuccessful in renaming the extension, so I am still in the same situation. I have tried creating the ringtone in outside programs such as ringtone creator and ringtone maker and the same result, and i have tried copying to my desktop and deleting old m4a file and making sure it is m4r. Any ideas? anything appreciated.

Thanks,