file upload problem in FCKeditor 2.6

hi there.

i've got a problem with uploading files (and images too) in FCKeditor 2.6. php version, it's installed in my Joomla CMS.
when i'm using it on my computer (Win XP) - it works perfectly.
but on the hosting it's appears the uploading progress bar...and nothing happens. file is not uploaded, and progress bar is not closing.
i test it in Opera, IE, Firefox, Chrome - it's all the same result - not working
i tried to set $Config[...] values manually - no effect.
all directory attributes are set to 777.

any ideas?