Using Vaadin 7 Themes in Liferay 6.1.2

Hi there,

I am struggling to get a Vaadin 7 (custom) theme to work in liferay 6.1.2.
Is there a docu somewhere how to do that?
On the one hand liferay’s portlet anatomy is to have a “css” folder and import the respective file in , on the other hand VAADIN organizes all the css theming in the VAADIN/themes/ folder …

… so, how do I combine one with the other?