Here is a description of the beer from the Dogfish website:
A modern update on a 9th century Finnish proto-beer. Brewed with rye, we caramelize the wort with white hot river rocks, then ferment it with a German Weizen yeast. In addition to juniper berries foraged directly from the Finnish country-side we added a sort of tea made with black tea, cardamom, cinnamon, ginger, cloves, and black pepper. The spicing is subtle and balanced and Sahtea is a highly-quaffable, truly-unique brew with a full-mouth feel.
|Image: Finlandia Sahti (source)|
Sahti is a traditional beer from Finland made from a variety of grains, malted and unmalted, including barley, rye, wheat, and oats; sometimes bread made from these grains is fermented instead of malt itself. Traditionally the beer is flavored with juniper berries in addition to, or instead of, hops; the mash is filtered through juniper twigs through a trough shaped tun called a kuurna in Finnish. Sahti has a distinct banana flavor due to the yeast. Sahti is a top-fermented brew (ale), and while baking yeast has been used traditionally, ale yeast may also be used in fermenting.Update, 5/19/2011: Read a New Yorker article published on November 24, 2008 about Sah'tea at A Better Brew: The rise of extreme beer, by Burkhard Bilger (hat tip Beertography).