Field settings

[David Squance]

How can I find out what invisible settings a particular field has?  I have
6 fields on a card which should have identical settings (except for
location and text content).  Looking through the Object inspector, there
appears to be no difference, yet I can get a text editing cursor(blinking
vertical line) in 3 of the fields, but not in the others.  Locking the
fields and then unlocking them made no difference.
Thanks,
Dave