How do you get around the ID and Version names in Oracle



I have an existing Oracle application with a client server front end written in fortran 77 on VMS. I want to use Grails to create a web front end and replace all the fortran with Java. Anyway each table already has a unique key column and version column. ie idkey and idkeyv. Each table uses an oracle sequence for the id field. I couldn't believe it when grails tried to add an id and version field with not null on an existing table of over 10 thousand records. It makes no since to do this even if it is required. I want to know if I can map the id to the existing xxkey column as well as the version to the xxkeyv column in each table. I can use another tool, but I kind of like Grails and would like to use it for this project. If anyone can help with this I would really appreciate it. Otherwise I have to switch to something else.