> I'm not sure *what* happens on win32 with devkit installed - it would
> be interesting to see if there is a 'types.conf' under the ffi lib
> directory after install.

after a gem update successfully grabbed 0.5.4 on my machine, no 'types.conf' file anywhere in the gem...

c:\ruby19\lib\ruby\gems\1.9.1\gems>dir /S /W ffi-0.5.4-x86-mingw32\types.conf
 Volume in drive C is OS
 Volume Serial Number is
File Not Found


...and to double check fumble fingering the command...

c:\ruby19\lib\ruby\gems\1.9.1\gems>dir /S /W ffi-0.5.4-x86-mingw32\extconf.rb
 Volume in drive C is OS
 Volume Serial Number is 

 Directory of c:\ruby19\lib\ruby\gems\1.9.1\gems\ffi-0.5.4-x86-mingw32\ext\ffi_c

extconf.rb
               1 File(s)          1,251 bytes