.......A Floating Point Exception Occurred In The User Process.........

I'm getting this error:

System.Data.SqlClient.SqlException: A floating point exception occurred in the
user process. Current transaction is canceled. at
System.Data.Common.DbDataAdapter.Update(DataRow[] dataRows, DataTableMapping
tableMapping) at ...etc etc

    when updating one particular table, but not when updating another using nearly the same code.

I've searched and searched on the inet, but with no joy.

Microsoft have several different manifestations of it, under various
different circumstances, but the solutions all seem to involve
installing SP4, which by the looks of it is a massive procedure that
you have to go to university to be competent to do.

In any case, according to Enterprise Manager, I already have SP4
included. On the other hand, the one file of mine I checked the date of
against MS's hotfix file list was 2002 not 2003, so who knows?

My Service Manager is v 8.00.760, and it's the Development Edition (ie it's all running on the one machine).

According to the info on sqlDataAdaptor.update,  the
sqlError that gets returned  as part of the sqlException contains
fields Class, which gives the seriousness of the error, and State,
which identifies the exact error.  I get Class=16 (user-fixable)
and State=1, which we have to go to SQL Books Online to discover the
meaning of.  SQL BO probably sounded like a good idea to W.Gates,
but it took me half an hour to get anywhere near finding out what that
'1' meant.  When I did, it was (guess): 'A floating point
exception occurred in the user process. Current transaction is
canceled.' !!!

Can anyone please tell me what exactly might be causing the error?

Graham Rounce