Carlos just sent me an excellent article by Marius Clore, published this year. It presents a highly-accurate method to calculate the expected molar extinction coefficients of proteins on the basis of the type and number of amino acids present, at a wavelength of 205 nm.
I have not only attached the Clore paper, but also the analysis of stathmin.
Punchline: epsilon_205 = 480480 M^-1 cm^-1.
Now... we have to find a UV/Vis spectrophotometer capable of transmitting and detecting 205 nm light. (I've asked Phil).
I remember using 205 nm on the big spec machines with a Quartz cuvette. I have attached the spec data. If I remember correctly, the absorbances @ 205nm was on the slope leading up to a peak at 215ish nm