Perl on Windows looks for the lib and site\lib directories relative to the location of the perl56.dll (or perl58.dll for Perl 5.8). So you would have to copy the lib and site\lib trees too. E.g. if your application (and perl56.dll) are in C:\usr\MyApp then you would need to move C:\Perl\lib to C:\usr\lib and C:\Perl\site\lib to C:\usr\site\lib.

Why don't you just leave perl56.dll in the C:\Perl\bin directory?