html hyperlinks show URL in brackets in Entourage

开发者_StackOverflowI have an email script written in .Net that sends html emails. The email uses normal html hyperlinks to insert a link in the email, like this:

<a href="http://www.stackoverflow.com/">StackOverflow</a>

The problem is that in Entourage, a hyperlink like this always shows up for me like this:

StackOverflow < http://www.stackoverflow.com/ >

How can I format the hyperlink in my email so that in Entourage the text "StackOverflow" is the actual hyperlink, and the URL is not displayed after the text? Is there an html meta tag that needs to be set? Do I have to set the content-type somewhere? Or is there a different html syntax on the hyperlink itself that I should use?

In emails from some websites a hyperlink such as the one above renders correctly in Entourage, whereas in emails from others it does not. So, what is the difference between the emails sent from these different domains?

I suspect it is something in the meta information. Maybe the DomainKey-Signature?