string and wide string usage

[Ali Bendriss <ali.bendriss@gmail.com>]

Hello,

I've got a small program that read some value from an ldap server and 
copy them in a posgres database.
the function reading the ldap value return an unbounded_string, then I 
use to_string to feed postgres (using gnatcoll).

I've got some problem with some string in example:
a base 64 encoded string
V2luZG93c8KgNyBQcm9mZXNzaW9ubmVsIE4=
wich decode to 'Windows\xa07 Professionnel N' in utf-8
every thing is working if I feed directly the database, but if want to 
apply Ada.Characters.Handling.To_Lower on the string before feeding the 
database postgres is not happy 
'ERROR:  invalid byte sequence for encoding "UTF8": 0xe2 0xa0 0x37'
it's not really a big deal, but I would like to understand where the 
problem is. Do I have to use wide string ?

thanks,

Ali