D-link EBR-2310 speed issue

Hi,

I have the following configuration:
- Cable modem with >12Mbps download and >1.5Mbps upload.
- The cable modem is connected to a Ethernet hub (10/100/1000) as well
as a computer (let's call it server) and the WAN port of the D-link
EBR-2310 router.
- Another computer (let's call it client) is connected to the LAN port
of the D-link router.

If from the client, I access the server via ftp or scp, I get a download
speed of roughly 2.5MB/s and an upload speed of 200KB/s. Since it is
not involving any internet connection between the two, I should get the
same speed both way.

But I found out that even though the server and the D-link router are on
the same subnet, all packets for that subnet coming from the LAN are all
redirected to my internet provider's gateway. This explain why I get
only 200KB/s as this is my provider upload speed. This also explain why
I'm only getting 2.5MB/s since everything is at least 100Mbps on my
network I should be getting about 10MB/s at least.

Is this a known issue of D-link routers? Is there an easy way to fix this?

Thanks in advance for the advice,
Manu