tls plugin and SSL version

I've seen some reports that qpsmtp fails some PCI compliance testing 
because it can be accessed via SSLv2.

http://en.wikipedia.org/wiki/Payment_Card_Industry_Data_Security_Standard

http://bugs.contribs.org/show_bug.cgi?id=6141

Here's a simple, and untested, patch - someone might care to do something 
more elaborate to allow choice of TLSv1 or SSLv3 (unfortunately 
IO::Socket::SSL doesn't seem to allow disable of just SSLv2).

--- qpsmtpd-0.83/plugins/tls.orig	2010-07-22 22:04:00.000000000 -0400
+++ qpsmtpd-0.83/plugins/tls	2010-07-22 22:09:35.000000000 -0400
@@ -80,6 +80,7 @@
     local $^W; # this bit is very noisy...
     my $ssl_ctx = IO::Socket::SSL::SSL_Context->new(
         SSL_use_cert => 1,
+        SSL_version => 'TLSv1',
         SSL_cert_file => $self->tls_cert,
         SSL_key_file => $self->tls_key,
         SSL_ca_file => $self->tls_ca,
@@ -176,6 +177,7 @@
         my $tlssocket = IO::Socket::SSL->new_from_fd(
             fileno(STDIN), '+>',
             SSL_use_cert => 1,
+            SSL_version => 'TLSv1',
             SSL_cert_file => $self->tls_cert,
             SSL_key_file => $self->tls_key,
             SSL_ca_file => $self->tls_ca,