Hi everybody!
Last time,my first gentoo could not have any sound.And I think i had tried every way .At last I had  a new  gentoo system,and it was OK with sound.Then i copy the /etc in my second system with sound to the fist system which is without sound ,and then my first gentoo is Ok with sound!
Then I updated in my second gentoo to gcc 4.0.2 and glibc2.4,and "emerge -e system && emerge -e world" and "etc-update" and update all the file.And when i reboot,error occured:"udev-event[1731]:find_free_number:%e is deprecated will be removed and is unlikely to work correctly.Don't use it." and "network unreachable".
 
After i logined,i typed:"ifconfig",it showed:
eth0      Link encap:Ethernet  HWaddr 00:E0:4C:8C:B8:C9  
          inet addr:0.0.0.255  Bcast:255.255.255.255  Mask:0.0.0.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:4712 errors:0 dropped:0 overruns:0 frame:0
          TX packets:2 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:392339 (383.1 Kb)  TX bytes:120 (120.0 b)
          Interrupt:11 Base address:0xc400 
lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)
 
But i checked the file resolve.conf,hosts,net ,it's OK!
And the system don't have any sound now ,i can't find the file "dsp" in the /dev.
Don't you think is so weird!
I think maybe there is some bug with the init script.