perlrun -aF

Hi there, I just have a little peculiarity that I am wondering about.

The following code works as expected:
#!/usr/bin/perl

while(<>)
{
     @F = split('');

     print map unpack("B8",$_),@F;
}

Test run:
tor% ./test.pl
abc
01100001011000100110001100001010*

BUT:
tor% perl -aF'' -ne 'print map{unpack"B8",$_}@F'
does not.

tor% perl -aF'' -ne 'print map{unpack"B8",$_}@F'
abc
01100001

Doesn't autosplit or -F work as described in perlrun?

Tried both Perl 5.005_03 and 5.8

Tor

* Need to add some spaces, but haven't figured out any
decent method yet. :)