[AccessD] Composite Unique Key in 2010

[Charlotte Foust]

I'm running into a problem I've never seen before.  When I try to create a
unique composite key, the options to check the unique property aren't
available.  This is on a client's machine running Windows 7 and Office
2010.  I've never seen this behavior before and it's making me crazy.  It
isn't just one table either, it's all of them.  These are new tables
created in 2010 on the machine.  It will allow me to create a composite
Primary key, but not a composite unique key.  Has anyone run into this
before?  I haven't in 20+ years of Access, so I'm baffled.  It's defaulted
to a 2007 accdb format if that makes a difference.

Charlotte