Sorting bug?
 

I have a range of data that 16 columns by several hundred rows. It uses
headers, and filtering is turned on.

The rows contain both data and formulas. The formulas reference a column
within the row, as well as named cells outside the range.

When I select the entire range, and sort it, the columns with the formulas
are not sorted. It appears to me to be a bug.

After the sort, the columns that were not sorted contain the error
indicating the surround cells have dissimilar formulas. It only occurs on the
rows which were actually moved with the range due to the sort criteria. If
the first few rows are already in the correct order for the sort, the error
does not occur.

To get around it, after the sort, I have selected the columns that were not
sorted, and filled from the top of the column to the bottom to re-copy the
formula into the cells effected.

Any ideas why this is happening?
--
Ross