Hi,
I am getting the above error when all I am doing is adding normal text data to a form which happens to include a file upload, but the error is not happening when I upload a file. It is happening when I add data to a text area to what is a varchar2 field, not when I upload a file. This is in Apex 4.2.4

If I just enter a single string of text, the data gets updated without error, but the text area is varchar2(4000) so I don't understand why I am getting this error. Below is data entry that is successful-- no error message, data is updated.
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Help on what to look at to find the cause of this error would be appreciated.
Pat