loosing wireless connection

[Alvin Smith <email@alvinsmith.com>]

My system:

Dell Inspiron 8000
Belkin Wireless Notebook Network Card F5D6020 VER. 2
Debian Sid

When I first boot, or when I first insert the PCMCIA network card into the 
computer, networking works just fine.  But after a period of non-use, I can 
no longer ping the gateway.  If I restart the network, or if I re-insert the 
card, networking works again.

What could be causing this?

Thanks,
Alvin

-- 
     "Come now, and let us reason together, saith the LORD; 
      though your sins be as scarlet, they shall be as white
      as snow; though they be red like crimson, they shall 
      be as wool."                     Isaiah 1:18