Too early to try Magento 1.5.0.0 alpha2

Magento 1.5.0.0 alpha2 出来了，我下载来尝鲜。可是，安装到第二步就进行不下去了。提示是：

There was a problem proceeding with Magento installation.

Please contact developers with error messages on this page.

Notice: Undefined variable: params in /path/to/magento/app/code/core/Mage/Core/Block/Html/Select.php on line 142

这挺令人失望的。