No init found

help!!

i not understand, because when load the Kernel-2.6 in my board the system=
 block on following message  

"Kernel panic - not syncing: No init found.  Try passing init=3D option t=
o kernel"
 
my filesystem contain the process init into folder sbin i build it whit a=
 busybox-1.1.3

...
mtdblock_open
ok
mtdblock: read on "cramfs" at 0x400, size 0x200
mtdblock: read on "cramfs" at 0x600, size 0x200
mtdblock_release
ok
mtdblock_open
ok
mtdblock: read on "cramfs" at 0x0, size 0x200
mtdblock: read on "cramfs" at 0x200, size 0x200
mtdblock: read on "cramfs" at 0x400, size 0x200
kernel panic........

thanks to all