\nI haven't encountered this particular GPL question before, but I\nimagine it must be solved as you predict, not through the paradox of\na notice clause changing the meaning and intent of the rest of the\nlicense. Most likely, section 1 would allow you to say for your new project\nProject Foo, Copyright (C) 2005\n This program is free software; you can redistribute it and/or modify\n it under the terms of the GNU General Public License as published by\n the Free Software Foundation, version 2.\nProject Foo includes code from Project Bar, available at <URL>,\nlicensed under GPL v2 or later. Project Bar's original copyright\nnotices are as follows ...\n
So there is some ambiguity, but the first impression of a good lawyer with extensive GPL experience (not legal advice, yada yada yada) matched mine.
Cheers,
Ben