oh that's a good point, i always wondered sometimes I get failed to connect with the newer clients even if my clientinfo.xml is correct. So probably it neglects data folder for connecting only. I know it still reads from the data folder but probably not reading the xml anymore. That's why some people use a .bat file to direct the client to read the xml file.
anyway, do you want your 2011-09-06 file to read from the data folder, or are you going to use grf?