Is FieldA a date, datetime, or string field? If it's a string field what is the format used to create the date?
Have to post more technical information if you want help.
If it is a date or datetime field, then fieldA = currentdate should work. If it is a string field, then you have to match the format, including time, with the totext function.
Check the Help on ToText and format strings for date
Cheers,
-LW