It's hard to tell without seeing the complete mail headers. But you may want to in the future to xxx out the ip's and the emails unless you want that info archived here or people like me prodding at it'
Your mailserver is answering as is should be:
micxz@:~> telnet xx.x.xxx.xxx 25
Trying xx.x.xxx.xxx...
Connected to xx.x.xxx.xxx.
Escape character is '^]'.
220 tux Axigen ESMTP ready
HELO
250 tux Axigen ESMTP hello
MAIL FROM:
someone@hotmail.com
250 Sender accepted
RCPT TO: johnh10000@localhost
250 Recipient accepted
DATA
354 Ready to receive data; remember <CRLF>.<CRLF>
Subject: HELLO JOHN - H - 10000
HELLO JOHN - H - 10000
.
250 Mail queued for delivery