Your fix sounds like an improvement.  However, on the Solaris system where I
saw the problem on build 66309, it looks to me (though my knowledge is
limited in this area) like locale en_US *is* present, so I don't see why
it isn't used.

Here is what I see on my Solaris 10 system:

stoat% cd /usr/lib/locale
stoat% ls -ld en_US*
drwxr-xr-x   3 root     bin          512 Apr 12  2006 en_US
drwxr-xr-x   9 root     bin          512 Apr 12  2006 en_US.ISO8859-1
drwxr-xr-x   9 root     bin          512 Apr 12  2006 en_US.ISO8859-15
drwxr-xr-x   3 root     bin          512 Apr 12  2006 en_US.ISO8859-15@euro
drwxr-xr-x  10 root     bin          512 Apr 12  2006 en_US.UTF-8

So why does estudio think locale en_US is not available?  Is there something
nonstandard about the directory name /usr/lib/locale (I thought I saw it in
the source code, with a comment about looking there for Solaris)?