Yes, thanks Keith, thats what I finally did.  I'm new to the 2003 SBS server,
and was surprised how difficult it was to find this answer.

I asumed that SBS was supposed to be easy(ier) for a Small Business Customer
to manage.  This issue started a couple weeks after the packaged Dell server
was installed, and repeats every week, sending out badly formatted warning
messages that cause the customer to be concerned that his server will crash.

There is no way for the customer to resolve this without some fairly expert
help.  Having to go in and "tune" the memory useage of SQL server using a
text-based tool like osql just seems to defeat the whole purpose of the SBS
product.  

Wondering if the problem might be a Dell install issue, as another thing
they did is create one tiny and one huge partition on the disk array, and
then installed all components of SBS on the tiny partition.  Within days
after the install the customer was getting low disk space warnings cause by
the Exchange email store......