that's exactly how we jack up our Foresters. There's a jacking plate on the front, under the engine, where you center the wood block or other protective pad. The wood block is used to protect the metal from being damaged by the floor jack.
Of course if you're going under the jacked up vehicle, it needs to be supported with jack stands, as floor jacks have been know to fail! :icon_eek:
Below is a picture from my member journal that shows the front floor jack point. It was being removed to install a front sway bar.
['07 FSXT MODding Journal
] ['03 X MODding Journal