[TYPO3] http://t3skin.spreekonzept.com/typo3/: Testing new skin does not work?

[seml at symbulos.com]

Dear friends,

every time we try to test the new skin at 

http://t3skin.spreekonzept.com/typo3/

we get the following error

Error: This host address ("t3skin.spreekonzept.com") and the 
referer host ("") mismatches!
It's possible that the environment variable HTTP_REFERER is 
not passed to the script because of a proxy.
The site administrator can disable this check in the "All 
Configuration" section of the Install Tool (flag: 
TYPO3_CONF_VARS[SYS][doNotCheckReferer]).

Could you please fix it?

-- 
symbulos uk ltd, co. no. 5441973, UK VAT reg no. 865302135
website http://www.symbulos.com