Cached Updates and BLOB in Oracle

I have a problem tring update a table with cached updates in oracle. When I
execute the aplly updates, occour the erro ORA - 22275.
I use the UpdateSQL the made the update.
When I switch the table without cached, the error don't ocour.

Delphi 5.0
BDE 5.1
Oracle 8.1.7
Native Access

TIA.