FTP problem

I used to have Serv-U as FTP server. And I could change directory like CWD /www/folderWe are now using MS-FTP and that gives me an error. The correct command is CWD www/folder (please note there is no leading slash)
I hava a piece of software trying to use the first command, but it throws an error. And changing the code is not an option, unfortunately.Is there any way to accept both ways of doing change directory? or someone has any tip for making this work ?Thanks in advance.