This is for the administrator of this site.
Your mail server appears not to be correctly set-up, as it is reporting itself as "ganesh.localdomain" which isn't a FQDN. Can you resolve this, as this may also cause problems for new registrations?
See mail server log below:
Mon 2008-12-01 19:21:20: [4329:2] Session 4329; child 2; thread 5732
Mon 2008-12-01 19:21:14: [4329:2] Accepting SMTP connection from [88.191.250.9:39127]
Mon 2008-12-01 19:21:14: [4329:2] --> 220-mail.lemonlainey.com ESMTP MDaemon 10.0.2; Mon, 01 Dec 2008 19:21:14 +0000
Mon 2008-12-01 19:21:14: [4329:2] --> 220 Unauthorised relay prohibited
Mon 2008-12-01 19:21:14: [4329:2] <-- EHLO ganesh.localdomain
Mon 2008-12-01 19:21:14: [4329:2] EHLO/HELO response delayed 5 seconds
Mon 2008-12-01 19:21:19: [4329:2] --> 250-mail.lemonlainey.com Hello ganesh.localdomain, pleased to meet you
Mon 2008-12-01 19:21:19: [4329:2] --> 250-ETRN
Mon 2008-12-01 19:21:19: [4329:2] --> 250-AUTH=LOGIN
Mon 2008-12-01 19:21:19: [4329:2] --> 250-AUTH LOGIN CRAM-MD5
Mon 2008-12-01 19:21:19: [4329:2] --> 250-8BITMIME
Mon 2008-12-01 19:21:19: [4329:2] --> 250-STARTTLS
Mon 2008-12-01 19:21:19: [4329:2] --> 250 SIZE 0
Mon 2008-12-01 19:21:20: [4329:2] <-- MAIL FROM:<www-data@lists.videolan.org> SIZE=1440 BODY=8BITMIME
Mon 2008-12-01 19:21:20: [4329:2] Performing PTR lookup (9.250.191.88.IN-ADDR.ARPA)
Mon 2008-12-01 19:21:20: [4329:2] * D=9.250.191.88.IN-ADDR.ARPA TTL=(54) PTR=[ganesh2.videolan.org]
Mon 2008-12-01 19:21:20: [4329:2] * Gathering A records...
Mon 2008-12-01 19:21:20: [4329:2] * D=ganesh2.videolan.org TTL=(50) A=[88.191.250.9]
Mon 2008-12-01 19:21:20: [4329:2] ---- End PTR results
Mon 2008-12-01 19:21:20: [4329:2] Performing IP lookup (ganesh.localdomain)
Mon 2008-12-01 19:21:20: [4329:2] * Error: * Name server reports domain name unknown
Mon 2008-12-01 19:21:20: [4329:2] ---- End IP lookup results
Mon 2008-12-01 19:21:20: [4329:2] --> 451 <ganesh.localdomain> is invalid or DNS says does not exist
Mon 2008-12-01 19:21:20: [4329:2] SMTP session terminated (Bytes in/out: 90/342)