POSIX 1e ACLs are all very wonderful and so and the big reason that they're wonderful is that you can specify default ACLs which say something like "every file created in this directory should be writable by group foo" That is, until the user creates them with a umask of 022 and the write permission is masked away.
I'm sure that POSIX had a good reason for this somewhere, but umask has never worked very well anyway. So here's a utility which fixes up files which were created with a bad umask. Run it like this
find path -print0 | xargs -0 acldeletemask