On the page settings, in advanced settings you can set the page/menu to open an external link (in link url at the bottom). However there seems to be no option to open that link in a new browser window (i.e. target="_blank") Can anyone tell me how I can achieve this? Thanks. 

I am afraid that does not work and I just get a javascript error when i click on the link. I tried
window.open('http://news.bbc.co.uk') and window.open(http://news.bbc.co.uk) in the textbox under 'Location: ( Enter The Address Of The Link )' with the 'Link Type:' being 'URL ( A Link To An External Resource )'

That didn't seem to work. I ended up on the net and used void(window.open('http://news.bbc.co.uk'));

Thanks for your help.