in reply to qr/string/ is not the same as qr/$var/ ?
This is not regular expressions problem, nor qr problem. If you try foo.pl as:
and domy $foo = shift; print $foo,"\n";
I know I didn't answer your question. Basically, it seems program arguments are quoted. Can't say why.[ambs@eremita tmp]$ perl foo.pl 'fo\o' fo\o