(Not really a perl5i issue but I wanted it to get remembered somewhere)
I commented on the REPL feature request here:
Add a REPL schwern#213 (comment)
with a workaround for using Devel::REPL's re.pl script with perl5i. I'm not sure if/where/how to document this especially since new versions of LexEnv might just make the issue go away.
Someone knowledgeable might add this to documentation or just make it part of a FAQ (Can I use Devel:REPL with perl5i?