ftp directory handling doesn't seem to work properly, sometimes results in multiple same name folders

[skygunner]

ftp directory handling doesn't seem to work properly, especially try to upload a folder,
which would normally create the folder and cwd into it. But the current behavior is upload a folder will usually create it, but CWD into it will fail.

Manually create a folder, then cdw into it works.

This sometimes results in multiple same name folders due to the client retry creating the folder.
Then if delete the folders sometimes you would delete the wrong folder due to client side caching maybe.