Oliver,
Your URLs resolve as follows.
tinytwo.net = 66.218.79.155 (yahoo.com)
mail.tinytwo.net = 64.230.157.111 (sympatico.ca)
www.tinytwo.net = 64.230.157.111 (sympatico.ca)
Note the different IP adresses!
Are you hosting your web site on your SME Server or remotely at Yahoo?
mail.tinytwo.net is being directed to the same IP address as your web site.
I can not telnet to mail.tinytwo.net on port 25 so something is wrong with the DNS or redirection service. OR your ISP is blocking port 25.
Below is some DNS information that might help you figure it out. You may also want to check with your ISP to see if they are blocking any ports.
DNS Lookup Results for tinytwo.net
Host Type Value
tinytwo.net MX 10 tinytwo.net
tinytwo.net MX 10 mail.tinytwo.net
tinytwo.net MX 10 mail.tinytwo.redirectme.net
tinytwo.net NS ns9.san.yahoo.com
tinytwo.net NS yns1.yahoo.com
tinytwo.net NS yns2.yahoo.com
tinytwo.net NS ns8.san.yahoo.com
tinytwo.net A 66.218.79.149
tinytwo.net A 66.218.79.155
tinytwo.net A 66.218.79.147
tinytwo.net A 66.218.79.148
ns9.san.yahoo.com A 216.109.116.20
yns1.yahoo.com A 66.218.71.205
yns2.yahoo.com A 216.109.116.20
ns8.san.yahoo.com A 66.218.71.205
DNS Lookup Results for mail.tinytwo.net
Host Type Value
mail.tinytwo.net CNAME mail.tinytwo.redirectme.net
tinytwo.net NS yns2.yahoo.com
tinytwo.net NS ns8.san.yahoo.com
tinytwo.net NS ns9.san.yahoo.com
tinytwo.net NS yns1.yahoo.com
DNS Lookup Results for
www.tinytwo.netHost Type Value
www.tinytwo.net CNAME tinytwo.redirectme.net
tinytwo.net NS ns9.san.yahoo.com
tinytwo.net NS yns1.yahoo.com
tinytwo.net NS yns2.yahoo.com
tinytwo.net NS ns8.san.yahoo.com
ns9.san.yahoo.com A 216.109.116.20
yns1.yahoo.com A 66.218.71.205
yns2.yahoo.com A 216.109.116.20
ns8.san.yahoo.com A 66.218.71.205