No legal Deoxys knows Aeroblast. Firstly, The 10th anniversary Deoxys distributed in Japan last year did not have any special moves. Likewise, Space Center Deoxys (distributed in 2006) and Dutch/DOEL Deoxys (distributed in 2005) reportedly had no special moves, either.
All other Deoxys originate from Birth Island (FireRed and LeafGreen's, if to be exact). In particular, there was only one event in the UK distributing Deoxys, and it simply could not accommodate special moves due to triggering the Birth Island event.
I believe that the source of this erroneous information is this YouTube video. The player's Deoxys (shown in 2:06-2:11) is clearly hacked (it is stated as much in the additional information section, albeit in regard to being Shiny), which can be derived from the fact that its OT is that of the player's, yet it still has a special move. This person may not have created the rumor, but they fueled it by boasting the accomplishments of hacking on the Internet. --Unown Lord 07:51, 8 May 2008 (UTC)