Is it possible to open a menu item in a new window (in drupal 5.0)?

IIRC the menu used to be (in 4.5 or so) just a list of links in html format so opening it in a new window was just a matter of adding target="_blank" however now the "Add menu" dialog asks for link and I don't see any setting that would make it possible to adjust how it's open.

TIA,

erik