Well, like it always goes, you make a new dress (from a new era) and you need new underclothes.  Luckily, this regency garment was not too difficult to come up with.  I designed it using the pieces from the Period Impressions 1809 Day Wear Pattern as a template and tailored them to fit me as well as to go under a gown without peeking out.  The top is lined with a light cotton canvas and has only two pieces of boning in the front.  I also added a casing around the neckline to accompany the one around the waist.  Although this garment is probably not very historically accurate, it gives the desired effect and worked well under the Cream Patterned Cotton Regency Gown with Half Sleeves and V-neck Front at PVR 2007.