Ha! The first time that I actually had problem with HPFS and large partitions! But, never really thought about it before that the limit was 64GB. But, is the limit the same for 386HPFS?
JFS I think supported up to 2TB or something like that. But hey guess that if 640Kb was enought back in the good old days I guess that 64GB was supposed to be enough as well.