Yes, the error log says that some timeout occurred.
2013-01-16 04:41:41,002  Orchard.Email.Services.EmailMessagingChannel - An unexpected error while sending a message to
firstname.lastname@example.org: ActionEmailSystem.Net.Mail.SmtpException: The operation has timed out. at System.Net.Mail.SmtpClient.Send(MailMessage message) at Orchard.Email.Services.EmailMessagingChannel.SendMessage(MessageContext
I guess I would have to check the source code of this php script