I have a cell which uses a custom time format like this:
h:mm:ss.000
Say for example I type a value into the cell like "3:49:58.766" (without the
quotes).

If I subsequently double-click in this cell, then hit return, the displayed
value changes automatically to "3:49:59.000" (without the quotes).

It appears that the double-click causes the value to be rounded up. How can
I prevent this behaviour? I'm using Excel 2002 (SP3), Windows 2000
Professional.