[Zope] webdav and windows : copying a file hang

Hi, Anybody experienced this problem ? When trying to use WebDav from a windows (2000 or XP) client, using the built-in webfolders function, i can create a folder and even rename it, but when trying to copy files in it , it toook aaaaaaaaages , such amount of time that, at first, i thought the process was stuck. I am doing Apache Proxying ... I tryied with Cadaver under linux and it worked straight away !! (could copy mutltiple files using mput) Any hint would help as my users are Only windows users ... :-( Thanx Seb