bad interaction of rassociative and tellsimp



Consider the following:

declare(zand,rassociative);

matchdeclare(var1,true);
matchdeclare(var2,true);
matchdeclare(var3,true);

tellsimp(zand(var1,zor(var2,var3)),zor(zand(var1,var2),zand(var1,var3)));

(%i1) zand(zor(a,b),c);
(%o1)                         zand(zor(a, b), c)
(%i2) zand(a,zor(b,c));
(%o2)                    zand(zand(a, b), zand(a, c))
(%i3)

Note that "zor" became "zand" ?????