Lack of A/B-antigen equivalent to Rhesus disease
So it turns out it can occur. It's called Hemolytic Disease of the Newborn (ABO), and according to the article (the relevant citations are a book and some journals to which I do not have access), it is very rare, and severe cases are even more rare. Apparently anti-A and anti-B antibodies are typically of the IgM isotype, which cannot cross the placental barrier. However, occasionally IgG is produced, which can cross. 

This is what causes the hemolysis in the fetus - if the mother is type O, and the baby is either A or B, the mother is exposed to unknown antigen and produces antibodies. If they happen to class-switch to IgG, they can cross the placenta and, if in large enough quantities, cause the opsonization and lysis of red blood cells.