"BLOB has been modified" BDE Error

In my Delphi 2.0 component I am getting a "BLOB has been modified" BDE error
from accessing a memo field using the AsString property.  The error code is
13058 ($3302) and occurs in TBlobStream.Read from a DbiGetBlob call.

I have my BDE manual but this error does not seem to be listed.  Does anyone
know what the problem may be?

John

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