Edit: I take it back. It's completely screwed. There's a # in the ID, and it though it works when you add the fragment to the URL in the address bar while you're viewing the page, visiting the link afresh makes it explode.
This seemed like an interesting challenge, so I ended up creating a bookmarklet that lets you link to a comment on a post url (not directly from the person's stream, however) by clicking on it.
It also accounts for the height of the gbar and googleplus navbar, since linking directly to the anchor tag puts the comment directly at the top of the page, behind both of those fixed elements.
https://plus.google.com/102150693225130002912/posts/PVZDD2N3...
Edit: I take it back. It's completely screwed. There's a # in the ID, and it though it works when you add the fragment to the URL in the address bar while you're viewing the page, visiting the link afresh makes it explode.
Nice work, chaps. :-|