The problem isn't that underlining is needed (this is just one possible solution), it's that the links do not stand out enough. The link color is a greyish blue on white/blue background -- both not much more outstanding than black text.
I do not care much for the actual solution details, but you might do at least something for it. Several users, myself included, underline the links manually to workaround the visibility issue.
Your global solution may be underlining, a recolorization, or really anything. You should pick a solution that makes links still easily identifyable as links.
-- Simon