There was a fear the two characters might get 'confused' and so Elias Toufexis had all his voice work scrapped, which was recorded over two years before Deus Ex debuted.
Most recently Elias starred in Ubisoft's Splinter Cell: Blacklist as a weapons dealer who becomes a rather reluctant prisoner of Sam Fisher. His voice is easily recognised.
"...I shouldn’t say this, but there’s a game called Far Cry 3, which I’m sure you guys know, where I had played Jason Brody. I played him for two years, did the voice and when Deus Ex came out they replaced me because they were nervous that… ‘we don’t want people playing this game and thinking of another game,’" Toufexis said at MCM Expo.
“It’s justifiable. It’s understandable, but my normal voice is what I used for that character too. So now it’s like I’m losing work because Jensen is so popular.” Just use your CASIE aug, Elias, and sweet talk yourself into the booth. How would the world look today had Adam Jensen played Jason Brody?