Are you using additional usergroups for people as well?
those usergroupid's will need to be included.
edit:
is that shoutbox anything posted on this site? or is it a separate script?
You could always try the other conditional.
HTML Code:
<if condition="$bbuserinfo[usergroupid] == X OR $bbuserinfo[usergroupid] == Y">
If you need to add more just make sure you follow the same format as in the example.