The system file locking implementation for WebDAV protocol in UCB is
now used by framework to lock the opened documents. The behavior in
this case should be close to case of system file locking for the files
from local file system.
Since OOo lock-file is not used in this case it is not possible to
detect who has locked the file. As in case of local file system, if
the file on WebDAV server is already locked, the user has possibility
to open it read-only, open an editable copy or cancel the loading.