for 4 different Perls built on Linux and 3 built on AIX/Unix computers and none of them had 32 or 64 in the response. I then looped on the %Config hash with 'grep 32' for all platforms and nothing looks consistent between Linux and AIX/Unix. If the original question was for Windows, I guess it works, but it doesn't seem to be a platform independent solution.
Just a heads-up...Ed
Update: After commenting, I reread the original post and you're solution was right on for windows.
"Well done is better than well said." - Benjamin Franklin