STDEVP problem?

Hopefully someone can help with this one...

We're including a STDEVP function in a query sent to a local Access DB
from a C# Application - with an OleDataAdapter. We're using Jet 4.0 OLE
Drivers - and have no problems on any machines with Access (or the
Access runtime) installed.

One user - who does not have any version of Access installed - is
having trouble with this particular query (i.e all the queries in the
application return a set of results for a graph - and the one with
STDEVP doesn't). They are running Windows 2K SP4. I have tried the
application on a clean Windows 2K3 Server and XP box with no problems.

Am I right in thinking it's somehow this Jet-specfic function that is
causing the query to return incorrect (i.e. null) values? I'm confused
as to exactly what needs to be installed for this function to work
correctly - and if it isn't working correctly, why no errors are being
encountered.

Many thanks

Phil Jenkins