repeater - extending range with mixed branded HW

I have a BenQ AWL-700 wireless router and 2 wireless laptops.
This configuration works OK

In order to extend the covered area, I have bought a D-link DWL 900AP+ that
should act as a repeater.
On the external packaging, it is claimed that the repeating mode should
work.
In the complete pdf manual however, it is stated that this mode would only
work with certain specific other D-link models .
D-link does not offer support for configurations with third party hardware.

The shop claims that they succeeded installing the D-link DWL 900AP+ as a
repeater with other non d-link items.


The 2 laptops see both wireless devices.
However, when the wifi connection goes through the D-Link, nothing appears
to be relayed to the router.


The D-link access point is configured as follows :

- no DHCP server (this functions is done by the wireless router)
- WEP encryption. The key number and the key itself were checked -
connection with the laptops tend to proves this.
- the LAN (as opposed to WAN) MAC address of the wifi router is entered as
the remote address to connect
- the MAC address of the D-link access point was added in the authorization
list of the router
- All devices are configured with the same SSID and are using the same
channel


Can someone help ?

Thanks.