[Dev-luatex] Max length of tokens?

Hi, what's the maximum length of things like \pdfcatalog in luatex (and pdftex)? I.e. how long can a token register get? We have a pdf where there are a multitude of entries made with \pdfcatalog and pdftex seems to chop the /Catalog at some point. The resulting pdf is quite broken. :-( Best Martin