Michel,
You say it is occuring only sometimes.
Could it be possible that the router is about to connect to the Internet
while your computer tries to resolve this address?
Look at connection timeout in the router config.
The connection is "nailed-up", so I don't think so.
I do have drops of connection with VO (PPPoE light going out on the router), but not
really often.
Another possibilty would be to configure the DNS
server directly on your
computer (so it does not use the DNS relay of the router).
The DNS servers of VO should be:
80.90.44.25
80.90.45.15
I will try that, but I don't like the solution because it is static.
Regards,
-pu