URL's in Dynamic Text Fields - Line Break Probs

[Immulsifier]

Hi Peeps. I am making a guest book at the moment where I want users to be able to post URL links in their message. I have some code in a PHP file which links to the MySQL Database where everything is stored. In the PHP I have the following:-

$message = preg_replace("'\[url\]([A-z]+://)(.*?)\[/url\]'",'<u><a href="\\1\\2" target="_blank">\\2</a></u>.',$message);
$message = preg_replace("'\[url\](.*?)\[/url\]'",'<u><a href="http://\\1" target="_blank">\\1</a></u>.',$message);
$message3 = preg_replace("'\+://)(.*?)\"?](.*?)\[/url\]'",'<u><a href="\\1\\2" target="_blank">\\3</a></u>.',$message);
$message = preg_replace("'\[url=\"?(.*?)\"?](.*?)\[/url\]'",'<u><a href="http://\\1" target="_blank">\\2</a></u>.',$message);
$message3 = preg_replace("'\[email\](.*?)\[/email\]'",'<u><a href="mailto:\\1">\\1</a></u>.',$message);
$message = preg_replace("'\[email=\"?(.*?)\"?](.*?)\[/email\]'",'<u><a href="mailto:\\1">\\2</a></u>.',$message);

Now this recognises [ url][ /url] just like this forum. However if I am to do this:-

[ url]www.flashkit.com[ /url]
[ url]www.flashkit.com[ /url]

When it outputs it does not retain the line break as I entered it. It outputs the urls as [url]www.flashkit.comwww.flashkit.com (\"?([A-Za-z) Has anyone else experience a problem like this?

Thanks for any advice offered.