>No guarantee that it is dairy free. O-U only means that it is Kosher, not
>that it is dairy-free. To be certain, it should be marked O-U Pareve.
>However, there is some ambiguity in the O-U labeling; it may be pareve and
>not marked as such, if it is assumed to be obvious that it is pareve (!?).
>Since barbeque sauce is intended for use mostly on meats, it is likely to
>be in that category. Still, a call to the manufacturer would verify this.

According to the OU website, O-U alone means pareve.  They claim dairy
and meat would always be explicitly noted, and that pareve is the default.
(See http://www.ou.org/kosher/policy.htm)

In practice, I have seen O-U products without the D that are dairy, but
only extremely obvious things like milk, cream, ice cream, cheese, etc.
I have never seen any other type of product marked just O-U which was not
pareve.  Usually they only explicitly say pareve when you would expect the
item to be dairy or meat, such as non-dairy creamer or chicken-flavored
bouillon).

I regularly use the plain O-U as a reliable indicator that the item is
pareve.  But if someone's life depends upon it, you should always call.
It is always possible for an item to be mis-labelled with an unauthorized
or incorrect kosher symbol. (See http://www.kashrut.com/Alerts/ and
http://www.ou.org/kosher/alerts/ for current listings of mis-labelled
products)

--Robyn