When I try to correct it by changing railcraft ids, recipes break.
EDIT: nevermind. it was from mystcraft using item ids below 256 in its config, which was messing with a recipe
Quote from Adi_Tetac
Quote from SillyBits
This question came up yesterday (i think, or was it the day before yesterday? nvm) .... some mods do add a 256 to those id's read from its config file ... caused by some vanilla code which always subtract 256 from a given item id
Thank you, that was it, adjusted the id above 256 and it was fine; seems minecraft doesn't allow item ids below 256. Last time I used mystcraft with railcraft I used direwolf20's config file and he had already figured out all the conflicts.