Reserved column names in Rails 3

I'm attempting to upgrade one of my sites to Rails 3 and I'm getting
the following error:

field_changed? is defined by ActiveRecord

The particular table it is referring to has a column named "field",
and I'm assuming that the error message means that I can no longer
have a column named "field". First, am I assuming correctly?

Two questions:

1) I just want to upgrade to Rails 3. Is there a way to get around
this problem. or do I need to migrate that table and my data to use a
different field name?

2) Is there a list of all the reserved column names so I can avoid
them in the future?

Paul