I have a spreadsheet, which I have imported data into. There are several date columns in it, coming from two different sources. On one type, the dates are right-aligned in the column, and the Custom Filters work fine (say, Date >= 03/01/2011). The columns from the other source, however, have left-aligned dates, and the Custom Filters do not work at all. The regular filter does work. I have tried formatting the columns so that they are the same as the ones that work, (Date - Type *03/14/2001), but they still stay left-aligned, and do not filter. Any suggestions?