Gnome-hint displays the following messages on start-up:   
The font "fija" does not support all the required character sets for the
current locale "es_AR"
  (Missing character set "ISO8859-1")
  (Missing character set "ISO8859-1")
The font ""-*-helvetica-bold-r-normal-*-*-180-*-*-p-*-*-*" does not support
all the required character sets for the current locale "es_AR"
  (Missing character set "ISO8859-1")
  (Missing character set "ISO8859-1")

Apply the following patch to es.po to fix this problem:
--- gnome-core.po.orig  Tue Jul  9 00:25:48 2002
+++ gnome-core.po       Tue Jul  9 00:26:16 2002
@@ -160,7 +160,7 @@
 msgstr "-*-fixed-medium-r-normal--14-*-*-*-*-*-*-*,*-r-*"

 msgid "-*-helvetica-bold-r-normal-*-*-180-*-*-p-*-*-*"
-msgstr "\"-*-helvetica-bold-r-normal-*-*-180-*-*-p-*-*-*"
+msgstr "-*-helvetica-bold-r-normal-*-*-180-*-*-p-*-*-*"

 msgid "-*-helvetica-medium-r-normal-*-8-*-*-*-*-*-*-*"
 msgstr "-*-helvetica-medium-r-normal-*-8-*-*-*-*-*-*-*"
@@ -3502,7 +3502,7 @@
 msgstr "utilidades de directorio"

 msgid "fixed"
-msgstr "fija"
+msgstr "fixed"

 msgid "gaspell Spell Checker"
 msgstr "Verificador de sintaxis gaspell"
-- cut here --

Actually, "fixed" shouldn't be i18ned as it's a font name.