[yocto] Howto use yocto meta-toolchain?

[Marco]

Hi,
after build meta-toolchain (for beagleboard, for example) I have this script

15:32 koan at quad:~/yocto-8-danny/poky/build
$ ll tmp/deploy/sdk/poky-eglibc-x86_64-arm-toolchain-1.3.sh
-rwxr-xr-x 1 koan koan 16143 2012-12-03 15:25 
tmp/deploy/sdk/poky-eglibc-x86_64-arm-toolchain-1.3.sh

Then I argued I had to launch it to install the Yocto toolchain, but I 
get an error

15:32 koan at quad:~/yocto-8-danny/poky/build
$ sudo tmp/deploy/sdk/poky-eglibc-x86_64-arm-toolchain-1.3.sh
[sudo] password for koan:
Enter target directory for SDK (default: /opt/poky/1.3):
You are about to install the SDK to "/opt/poky/1.3". Proceed[Y/n]?
Extracting SDK...done
Setting it up...find: `/opt/poky/1.3/sysroots/x86_64-pokysdk-linux/lib': 
No such file or directory
SDK could not be set up. Relocate script failed. Abort!

What's wrong?
I wasn't able to find any document about it in YP website.

TIA
-- 
Marco