Sulfur Smell in Fermenting Beer

I have an Alt in the fermenter. The gas passing through the air lock originally had a normal hoppy, malty, yeast smell. After a couple of days the gas has taken on a sulfury - mild rotten egg odor.
I used a packet of Wyeast European Ale 1338, that was over a year old. The smack pack swelled up after 3 days, and I made a starter, which looked and smelled normal.
My sanitation is very meticulous. The only week link in my process is my aerator (a fish pump) that doesn`t have enough power to use an in-line filter.
This is the first time I`ve brewed this Alt and used this yeast strain. Is this smell anything to be concerned about?

Sulphur like smells emanating from fermenting wort are quite common, and their level or intensity is related to the srain of yeast being used. As a professional brewer I can attest that German Hefeweizen strains are extreemly sulphitic in nature. As far as the Wyeast 1338 strain goes, we use this strain for 3 of the beers in our brewery. It does tend to produce some sulphur aroma`s during fermentation, but these do not persist. This yeast does give a very clean finished product with out the estery solvent production that you would get with say Wyeast 1187 (Ringwood Ale yeast). Another advantage for the home brewer is that this yeast is a good floculator and your Alt should clear up pretty well.

I fermented a cider this fall using a Montrachet Red wine yeast and it stunk up the whole basement. A few weeks later you couldn`t keep the neighbor ladies away from the stuff. www.draftbeerstuff.com Supplying professional draft beer equipment and advice to homebrewers