Needing help!

I'm migrating my server's operating system from NT Server 4.0 to a Red Hat Linux 7.1.
Server cannot be down anytime, so I'm using another machine to install and configure Linux and Samba.
Linux and Samba server seens to be OK, but I simply can't copy the files from the NT server's share to my linux server using smbclient. All filenames that have special characters (I'm from Brazil and my language use some) causes an error "ERRDOS - ERRbadfile (File not found.) opening remote file <path and name of file>". With filenames that not contain special characters, it works fine.
Although I've read tons of documentation and faqs and made lots of changes in smb.conf, my situation doesn't change.
I'm looking for someone that has the same problem, for a final solution or, at least, talk about.

Thanks,
Leandro Collin de Castro.