[OpenAFS] changed meaning of permissions?

[Thomas Mueller]

Hello,

we used to have a directory with this ACL entry

   system:authuser li

so that users with a valid token may drop their files here, but no-one
will be able to read, modify, delete or overwrite existing files.
With the 1.4 clients this works fine.

Now I found that the 1.5.18 client (on Windows - no other versions 
checked) requires that the "w" permission must also be set to insert new 
files - but this allows the modification of existing files too.

Are my observations correct?
If so, was it intended and why? 

Thomas.