The two problems mentioned above have now been fixed in r71715.

There are (at least) two remaining problems with the round function in 2.x 
that I'm not going to fix, because the added complication doesn't seem
worth it.

(1) round(x, n) doesn't give correct results with large values of n;
    but small values (e.g., abs(n) <= 50) should be fine unless x is
    huge.

(2) round(x, n) still occasionally rounds the wrong way in borderline
    cases, even for small n.

Closing (again!)