For the record, I don't have a NWNdb account.
Btw. i understand what you feel... but maybe it would be easier to send a PM to a DM explaining why you want to bend the rules
i'm sure if you will make some good RP history of your character explaining your character evolution they will allow it
something like a ranger following his codex but eventually concentrating to much on melee combat (here come fighter 4 levels) which leads to loosing his ranger way of life (no more ranger feats, no more better animal companion) later after living in the wilderness and concentrating on melee combat he becomes more of a savage fighter (here come 5 lvl FB)