[O] Vertically aligning images in tables?

[Peter Davis]

I'm trying to place three images side-by-side to they're top-aligned, but I 
can't see to find a way to get org-mode to do this. My
current code is:

+----
| #+MACRO: p  \includegraphics[scale=.3]{$1}
| #+ATTR_LATEX: :align {p{5cm} p{5cm} p{5cm}}
| | {{{p(./A.png)}}} | {{{p(./B.png)}}} | {{{p(./C.png)}}}   |
+----

As far as I can tell from LaTeX doc, the p attribute is supposed to top-align 
the contents, but it's not doing that.

Have I missed something?

Thanks,
-pd