Invalid date/time value

[MCM]

Hello,

I am using Access 2003 to track avian monitoring data. I have created data
entry forms that record the date and conditions for each observation.

I have a textbox bound to "ObsDate" that has an input mask of 99/99/0000;0;_
Whenever I enter a date I get the error "The value you entered isn't valid
for this field." However, if I enter the same date in the table directly I
get no errors.

Help??

--Melanie