I have this observation on when I read your post. First, the error I am getting seems to be different on my version, "perl 5.10.0 for MSWin32" when I run your code, I think the "not scalar dereference" or "not private variable" don't really reflect the same thing (that is debatable as I want to garner views on this from our revered monks).

A "variable" can be any one of the Perl variables we know of and in this case perl thinks it is supposed to be "private" -When I read your post I thought you were making a private subroutine to another subroutine- and which you just happened to not dereference as it should have been. Whereas a "scalar" is a sigil-preceded entity so in your case perl thinks you're passing a scalar dereference which might not be clear enough of a message !.

That's just an observation which I hope I can stand corrected and be clarified about.

#replicating the Origianl Post (strictures on):

my $coderef = sub {print "Hi There \n";};
sub doit(&){          
    &{$_[0]};
    }
doit($coderef);     #accessing a code ref from within a subroutine
                    #Without prototype-check disabling..
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#The same perl complaint is generated in the above code too

C:\Documents and Settings\m>perl -
sub testit{ print 'hi' };;
sub doit (&) { $_[0]->() };;
my $codeRef = \&testit;;
doit( $codeRef );;
__END__
Type of arg 1 to main::doit must be block or sub {} (not private varia
+ble) at -
line 4, near "$codeRef )"
Execution of - aborted due to compilation errors.
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