Strange, with 1.0.1e (same as I'm using) I didn't have any problems, but I didn't specifically test with Outloook other than 2007. I did see plenty of users sending mail. I personally just tested with Thunderbird. I'll run another test tonight after hours and see what happens.CENTOS 6.6 x86_64, OpenSSL 1.0.1e-fips
If I add +no_tlsv1 to my exim configuration, none of our email clients are able to send through the server.