use bytes

I'm confused, can someone tell me why:

    #!/usr/bin/perl

    use bytes;
    $x = chr( 400 );
    print "Length is ", length( $x ), "\n";

prints 1, while

    #!/usr/bin/perl

    $x = chr( 400 );
    use bytes;
    print "Length is ", length( $x ), "\n";

prints 2?

% perl -v 

This is perl, v5.8.2 built for i686-linux

//Ed