Sorry, I wasn't clear and neither is the comment that I quoted. PERL_moreoptions() is passed a string (not, for example, a list of strings) and it doesn't handle quotes. What I meant to describe is that PERL_moreoptions() doesn't look for a new option after seeing a space after "-M" nor after "-m". Either that needs to happen or PERL5OPT needs to be split on whitespace and the resulting values passed ot PERL_moreoptions() one at a time.

I would think that PERL_moreoptions() should be looking for spaces, otherwise it needs to be renamed PERL_onemoreoption().

I'm sorry that this is a very quick reply as duty calls. Obviously more research is needed.