PCMCIA AND DHCP HELP

[zhenghao zhang alcatel com hk]

Hi, everyone
         I installed RH6.0 in my notebook and I can use the Xircom
Ethernet /Modem card to browse the Internet, send,receive e_mail when I
specify a IP address in  
the file /etc/pcmcia/network.opts.
        But the problem is that when I want to  use the DHCP sever to
assign IP address(I change the option of DHCP in the
/etc/pcmcia/network.opts),I get no
IP address and there no dhcpcd run in the system.  
       So I run the dhcpcd command in the shell and I got the error
message like dhcpcd[731]: ioctl SIOCSIFBRDADDR (ifConfig): Cannot assign
requested address  in the file /var/log/messages.
      Who can help me?
      Thanks a lot!