[imp] sub-folder problem: can't create mailbox node..

[Florin Iancu]

Hello,

Please tell me if you know something about this:
When one of my users try to create a sub-folder, an error like this is
displayed:
 The folder "example" was not created. This is what the server said:
CREATE failed: Can't create mailbox node /dev/vide/: Permission denied
For other users, it is possible to create sub-folders but not for all of
them.

Thanks a lot,
Florin
(I have Horde2, IMP3, PHP4.11)