Very slow performance with gigabit network

Hi all.
I have a problem with the cifs module in my gigabit network. I get the following performance:
95 mbytes/s with FTP
65 mbytes/s with samba, windows 7 client
8 mbytes/ with the cifs module on opensuse 11.4

I have tried all the solutions found on google,
such as directio, modifying rsize and wsize, with
no improvements. Any advice?

I started asking around collegues and others, on the internet too, and I found that almost everybody I know have performance problem with cifs.
If needed, I can test some new version of the driver to help your job.
I am a C programmer, even if I am not a kernel programmer and I don't know the CIFS protocol

JM