spacefly

Hi,
Can anybody help?...
I want certain people to have access to my ftp server and webspace, but is there any way to password protect individual route / top level folders, rather than actual URLs (which I can protect, but all html etc. content is also contained in it's own folder). (and no, I don't have the option to give other users individual ftp pswds).
i.e.
ftp.xxx.xxx
/downloads
/htdocs (all web content in here to which I can pswd protect individual urls contained in this folder)
/other
So for example I may want people to have access to /other, but I don't want them to have access to /htdocs else obvioulsy they could delete the contents etc. etc.
Any ideas?
Cheers
SF