Rich Text Field help

HI, Our company is in the process of upgrading our users from 5.8 to 6.5. In one of our applications when a person attaches a document to a rich text field in 6.5 and another user tries to open the attachment in 5.8, they get the error ‘note item not found’. The first symptom was that he was unable to open attachments created by others and saved in our Work Request documents in the log. The further issue was when he created an attachment, no one else was able to open it. The attachment icons were present, but there didn’t appear to be linked files behind them. He has been regressed back to 5.0.11 and all is normal again. If anywone has any information as to why this is happening, I would greatly appreciate some help.

Thanks

Deb