Organisation structure

Hello Everyone,
Concerning Bonita's organisation is it possible modify the type/length of customized fields ? I've read that in Studio we can add fields to have more information of our organisation but I realise that the length by default is 64. I've modify a test field in my case on Postgresql on custom_usr_inf_val to enlarge the length of my field for example 1024, but when I try to put information longer than 255 engine gives me an error in log(ERREUR: valeur trop longue pour le type character varying(64)). I think perhaps is there a kind of tool to force the attributes or it's a limitation on community version. Anyone knows? Or it's an error of type of field that I've tried.

Thanks in advance!

Wr.