Hello Henk Boen,
In order to set up things to work with OpenAccess you can create a trigger on insert of a row and set the value of the ID column using the Oracle sequence. You should specify the 'AUTOINC' key generator for the class,using the Forward mapping wizard.
During runtime, OpenAccess will use the sequence generated ID value to maintain object identity.
Hope this answers your question.
the Telerik team