It seems very confusing about which is the correct measurement for widescreen. Some places state its 1048 x 576 others 1050 x 576 but many state 1024 x 576. Even after effects up until cs4 had the aspect ratio resized to 1024 x 576. There is an aspect ratio calculator here that also states 1024 x 576
http://www.digitalrebellion.com/pixel_calc.htm
i'm going to go with that the correct resizing is in fact 1024 x 576. It isn't only the Star Wars DVD that matches perfectly with its HD counterpart. Just checked dorian gray PAL DVD against its Blu-Ray 1080p counterpart and that matches perfectly too.
WINDVD also resized PAL widescreen to 1024 x 576 so it seems that many players use this standard