[gps-users] GPS Editor displaying symbols incorrectly

[Roger Mc Murtrie]

I have just upgraded my gnat installation using
 gnat-2012-x86_64-apple-darwin10.8.0-bin
which installs
GPS 5.1.1 (20111220) hosted on x86_64-apple-darwin10.8.0
GNAT GPL 2012 (20120509)

The GPS editor now displays non-alphanumeric symbols incorrectly.
For example

  procedure Form_Basis_Set_Map (Source_file : in out tFile_Type;
                                Basis_Set   : out tBasis_Set_Map;
                                Error       : out tSource_Data_Error);
is displayed as:
procedure Form_Basis_Set_Map Source_file  in out tFile_Type,
                                Basis_Set    out tBasis_Set_Map,
                                Error        out tSource_Data_Error:,
It seems to be only the display of characters that is wrong; the correct characters are actually "there" as the correct form above was copied and pasted from what was displayed as the incorrect form.
How do I fix this?
Any help will be appreciated.
Roger