The License was changed recently to GPLv2.
Now, with the GPLv2, it is possible to use Aloha freely in most websites/webapps. You don't distribute your website/webapp and therefore are not bound by the GPLv2 to divulge your website's source code.
The GPLv2 _would_ take effect if you distribute your website in the traditional sense - a package that someone can run himself.
(IANAL and can't speak for Gentics etc.)