package Your::Module::Bytes;
use bytes;
do $INC{"Your/Module.pm"} . ".pl";
1;

##</code><code>##

package Your::Module::Unicode;
no bytes;
do $INC{"Your/Module.pm"} . ".pl";
1;

##</code><code>##

package Your::Module;
sub import {
    # require the desired submodule
    # dispatch import to that submodule
}