Rick,
If using SAS/IML , could try :

proc iml;
X = {0.4 1.0 1.2 1.7 2.6 2.7};

object =j(1,ncol(X));
coef = X;
b = X[+]/2;
rowsense = {E};
cntl = -1;
call milpsolve(rc,objv,sol,relgap,object,coef,b,cntl,,rowsense);
print objv, sol (X`)[l='X'] , relgap;
quit;