First, discussion about my PEP has diverted from the issue I'm trying to solve (I really just want %s fixed). While trying out Guido's suggestion to change str(), I ran into a kernel bug (I was running a -mm kernel that seemed to have something wrong with mmap). After rebooting into an older kernel, I ran into with what seemed to be GCC 4.0 miscompiling certain parts of Python (e.g. cPickle and unicodedata). Recompiling with GCC 3.3 seemed to fix things. Well, at least the unit tests were passing. I tried running a relatively big application. It crashed. After reverting my str() change the application still crashed. I suspected the generator expression changes so I reverted them. The application worked. I re-applied my str() change. The application still works. Time to call it a day.
I finally spent some time today and got my Windows laptop to print. It seems the root problem was due to SMB browsing not working over a wireless link. I didn't dig into the details but just added the server to the lmhosts file. The stupid detail that likely wasted most of my time was that I had to reboot Windows XP in order for things to start working. Microsoft has made some progress on eliminating the need for many reboots but obviously have not been completely successful.
Also, I had to write a little Python print filter to remove the extra junk that the Window's PostScript driver inserts (i.e. "LastPage", "ProductName:", etc.).