Just a caution...it seems to me very likely that those two directorys were established by different perl installs and that those different perls are very likely to be binary-incompatible.

Be aware of that and check that any non-pure-perl module you use is built for the actual perl you are running. (Modules that may be a problem should be in an architecture-specific subdirectory that would prevent you from getting the wrong flavor of module, but whoever installed things could have overridden that. Anyway use lib will automatically add those subdirectories if it thinks it can, based on the settings of the Config module it finds.