upgrading and loosing rubber

  • as per a previous support post i have upgraded all my mods and client to 1.6.4. (using IC2 exp 397). i also converted the cfg file by hand coding to match the new block id's so i could try running an old game save. when i load it up everything is good except all my rubber trees are gone. i went travelling to some new chunks (so i could see if any rubber spawned. i was only able to find 2 rubber trees in almost a 2000blockx2000block area) any ideas how i can solve the rubber problem?