Having problem with SPARK Ada complaining that 'No EXPRESSION can start with reserved word "OTHERS".'

[Ben Hocking <benjaminhocking@gmail.com>]

The following is a simple test program to demonstrate the issue.
test.ads:
====
package Test is
   type QState is (Off, On, Both);
   subtype Z4 is Integer range 0 .. 3; -- 0, 1, 2, or 3
   type Ensemble is array (Z4) of QState;
   procedure Foo;
end Test;
====
test.adb:
====
package body Test is
   procedure Foo
   is
      SomeQState : Ensemble := (others => Off);
   begin
      null;
   end Foo;
end Test;
====
When I use SPARK->Examine File (from GPS), I get the following message:
  4:33     Syntax Error  No EXPRESSION can start with reserved word "OTHERS".
I get the same error if I type "spark test.adb" from the terminal window (I'm on Mac OS X 10.6.8).

I know this is valid Ada, because this compiles without issue:
gcc -c -g -gnatQ -gnato -fstack-check -g test.adb

I've tried this with both SPARK95 and SPARK2005. I'm using the AdaCore tool chain. The version information for SPARK is:
$ spark -version
           *******************************************************
                              Examiner GPL 2011
             Copyright (C) 2011 Altran Praxis Limited, Bath, U.K.
           *******************************************************

Any help would be appreciated!