adding anchor tags to urls

[jdc44]

does anyone have a regular expression that will add anchor tags to a url in text?

Example: If I enter into a form http://www.johndcowan.com/, I'd like to change this to <a href="http://www.johndcowan.com/"</a>

Thanks for any help.
jdc44

[jdc44]

opps!
I meant that I'd like my url to become <a href="http://www.johndcowan.com">http://www.johndcowan.com/</a>

Thanks,
jdc44

[bike5]

Extract out the value between the preset tags to define a url. Reconstruct a variable like

$extracted = value between the tags
$new = "<a href=\"$extracted \">$extracted </a>";

Im sure theres other ways to do it too.