V4 comes with a series of magnets that can help clothing conform better and remove most poke-through. It is applied after you pose V4 and conform to her clothing. However, as RedPhantom posted, the morphs need to be present in the clothing, and the only way to accomplish this in P11 and P12 is to copy those morphs using the Copy Morph feature.
As a matter of clarification, Poser does not auto-conform clothing unless you drag and drop the content onto the figure. You can simply load clothing into the scene by either double-clicking the Library icon or using the check icons on the bottom of the Library.