migrating from firebird 2 to 4

migrating from firebird 2 to 4

I use dbx with dbexpress driver I am migrating from firebird 2 to firebird 4 and it returns the error:

type mismatch to field 'QNTSAI', expecting :FMTBcd actual : Float

I need a way to use both versions until I migrate all the databases

delphi11 with dbxida_6.1.1