Now you lost me, caitlyn. Are you saying that my attempt with vpackager didn't work because I don't have Fortran, or the right Fortran installed. After I got the original 777 error, I followed rbistolfi's instructions, got what I thought was the compiler and ran it again. As far as I could tell, there was no error message, but no .tlz file either. As I noted earlier, there is a folder under /tmp/vpackager-builds, called R-2.8.1 with a lot of files and folders in it. That and the lack of an error message suggests that I was successful, but the absence of a .tlz file and R not starting from a Terminal (I tried from su as well) suggests I wasn't.
I'm going to trash that folder and start over again. How do I use pkgtools to install the file (i.e., what command do I issue and do I have to be in a certain directory to make it work)?