Calc Guide

Figure 48: Choosing the criteria and order of sorting
Figure 49: Options for sorting
Case sensitive
If two entries are otherwise identical, one with an upper case letter
is placed before one with a lower case letter in the same position if
the sort is descending; if the sort is ascending, then the entry with
an upper case letter is placed after one with a lower case letter in
the same position.
66 OpenOffice.org 3.x Calc Guide