WLAN shielding

Apologies in advance if this may not quite be the proper list for such a question... My company is investigating the use of wireless in a couple of our conference rooms. Aside from limiting the scope of reception with various directional antennae, does anyone have any suggestions or pointers for other ways to limit the propagation of signals (i.e. special shielding paint, panels or other wall coatings)? Feel free to reply off-list. Thanks! Andy --- Andy Grosser, CCNP andy at meniscus dot org ---