** SOLVED ** That was it! Russo Elio 27.Nov.07 11:15 AM a Web browser Administration 7.5.1 CF1Windows
That was it. I had the Client-to-Client option enabled.
I disabled it and the 751 connect client started to obey the maximum file size limitation.
This might help someone else save some time: since the maximum file size can be set in two places, in the Community Services section of the server's configuration and also in the policies, the result is a combination of the two.
The setting in the Community Services section of the server's configuration is the absolute maximum size users can transfer, even if the policy specifies a higher size. So I guess the size to specify in the policies should always be less or equal than the size set in the Commuity Services setting.
Provided that client-to-client file transfer is disabled ....