Dual port memory corruption

I just looked at this doc and the section "Mixed-Port RDW" suggests that you can't use a dual clocking scheme with mixed ports and the old data option all at the same time: http://www.altera.com/literature/ug/ug_ram_rom.pdf

If that's really true then that's a bug with the on-chip memory component. If this is true I'm not sure why Quartus allowed the compile to go through unless the memory component does something to the instantation that makes it work.