oof, yes, i seem to have lost some of my perl-fu. i've recently been drawn to the dark side, aka functional languages.
But I shortened my program even more

sub stest
{
    my $str = shift;
    foreach (@_) {
    substr($str,$_-1,2) =~ /^(10|01)/ || return;
    }
    return 1;
}

#USE: stest( $bit_string, @indexes )
[download]