When creating federated objects, you can use the sample forward type mapping provided for Oracle.
CREATE TYPE MAPPING FROM LOCAL TYPE timestamp(0)
TO SERVER TYPE oracle REMOTE TYPE timestamp(0);
CREATE TYPE MAPPING FROM LOCAL TYPE timestamp(1)
TO SERVER TYPE oracle REMOTE TYPE timestamp(1);
CREATE TYPE MAPPING FROM LOCAL TYPE timestamp(2)
TO SERVER TYPE oracle REMOTE TYPE timestamp(2);
CREATE TYPE MAPPING FROM LOCAL TYPE timestamp(3)
TO SERVER TYPE oracle REMOTE TYPE timestamp(3);
CREATE TYPE MAPPING FROM LOCAL TYPE timestamp(4)
TO SERVER TYPE oracle REMOTE TYPE timestamp(4);
CREATE TYPE MAPPING FROM LOCAL TYPE timestamp(5)
TO SERVER TYPE oracle REMOTE TYPE timestamp(5);
CREATE TYPE MAPPING FROM LOCAL TYPE timestamp(7)
TO SERVER TYPE oracle REMOTE TYPE timestamp(7);
CREATE TYPE MAPPING FROM LOCAL TYPE timestamp(8)
TO SERVER TYPE oracle REMOTE TYPE timestamp(8);
CREATE TYPE MAPPING FROM LOCAL TYPE timestamp(9)
TO SERVER TYPE oracle REMOTE TYPE timestamp(9);
CREATE TYPE MAPPING FROM LOCAL TYPE timestamp(0)
TO SERVER TYPE oracle REMOTE TYPE date;