Mercury with Xamp does not mail, but gives no error

Question

Im making a website, and after users have registered i want to send them an email. Im using the codeigniter framework which has some neat premade mail functions in it. The code is working like it should, and when i run the php mail debugger it says this :

220 localhost ESMTP server ready. 
hello: 250-localhost Hello localhost; ESMTPs are:
250-TIME
250-SIZE 0
250 HELP
from: 250 Sender OK - send RCPTs.
to: 250 Recipient OK - send RCPT or DATA.
data: 354 OK, send data, end with CRLF.CRLF
250 Data received OK. 
quit: 221 localhost Service closing channel.
Your message has been successfully sent using the following protocol: smtp
User-Agent: CodeIgniter
Date: Sun, 26 Aug 2012 01:50:52 +0200
From: "Free Interesting Articles" 
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As you can see there are no errors, but i never recieve the email.. Ive setup the mercury mailserver that comes with xampp, and it logs every mail i send, but i dont recieve any emails at all.

Does anyone have any idea's on how to fix this?

Thanks!