Sorry for the false start. I encountered the problem when I played with it last year, and forgot how I got around it.

I 'fixed' it, by patching 3 lines/ 3 chars in the module:

use strict;
use Hook::LexWrap;

=comment

    With Hook::LexWrap patched as follows:
    
39:             () = $wrapper{pre}->( \@_,$return) if $wrapper{pre};
49:            my $dummy = $wrapper{pre}->( \@_, $return) if $wrapper{
+pre};
59:            $wrapper{pre}->( \@_, $return) if $wrapper{pre};

=cut


sub some_sub{
    print "Got: @_\n";
    print "Context: ", defined wantarray 
        ? wantarray 
            ? 'LIST' 
            : 'SCALAR' 
        : 'VOID', "\n";
}

sub before{
    # inject a new arg
    unshift @{ $_[ 0 ] }, 'new arg';
}

wrap some_sub, pre =>  \&before;

my @a = some_sub(1,2,3);
my $a = some_sub(1,2,3);
some_sub(1,2,3);

__END__
P:\test>junk4.pl
Got: new arg 1 2 3
Context: LIST
Got: new arg 1 2 3
Context: SCALAR
Got: new arg 1 2 3
Context: VOID
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The caveat is that your wrappers have to expect a reference to @_ and deal with that. Not a major problem, if you need to make modifications.