Sweave and typeface control

Sweave has a tendency to preclude latex packages from setting typefaces, apparently. Here’s a much simpler fix (R 2.3.0+) than my hacky solution of using \input or \include to typeset the sweave-generated file in a wrapper file. (I suppose I should upgrade my R installation so that I can actually use this, but I shudder at the thought of updating all those packages again. I’ll put it off for just a few more weeks, I think.)