diff --git a/data/i18n/praxis_el.properties b/data/i18n/praxis_el.properties
index 911513ce4a5ee08e16ec1583a4374c7bde243f5f..e2b7f3802d100013cb4f6bb3789556fc182b79a4 100644
--- a/data/i18n/praxis_el.properties
+++ b/data/i18n/praxis_el.properties
@@ -130,6 +130,9 @@ UI.dialog.prg_properties.main_label                   = \u03a0\u03b5\u03c1\u03b9
 UI.dialog.prg_properties.parameters                   = \u03a0\u03b1\u03c1\u03ac\u03bc\u03b5\u03c4\u03c1\u03bf\u03b9:
 UI.dialog.prg_properties.parameters_default           = (\u03ba\u03b1\u03b9 \u03b7 \u03c0\u03c1\u03bf\u03b5\u03c0\u03b9\u03bb\u03b5\u03b3\u03bc\u03ad\u03bd\u03b7 \u03c4\u03b9\u03bc\u03ae \u03c4\u03bf\u03c5\u03c2)
 UI.dialog.prg_properties.title                        = \u0399\u03b4\u03b9\u03cc\u03c4\u03b7\u03c4\u03b5\u03c2 \u03c0\u03c1\u03bf\u03b3\u03c1\u03ac\u03bc\u03bc\u03b1\u03c4\u03bf\u03c2
+UI.dialog.prg_properties.invalid_value                = \u039c\u03b7 \u03ad\u03b3\u03ba\u03c5\u03c1\u03b7 \u03c4\u03b9\u03bc\u03ae
+UI.dialog.prg_properties.invalid_integer_value        = \u039c\u03b7 \u03ad\u03b3\u03ba\u03c5\u03c1\u03b7 \u03c4\u03b9\u03bc\u03ae: \u03b1\u03c0\u03b1\u03b9\u03c4\u03b5\u03af\u03c4\u03b1\u03b9 \u03b1\u03ba\u03ad\u03c1\u03b1\u03b9\u03bf\u03c2 \u03b1\u03c1\u03b9\u03b8\u03bc\u03cc\u03c2
+UI.dialog.prg_properties.invalid_float_value          = \u039c\u03b7 \u03ad\u03b3\u03ba\u03c5\u03c1\u03b7 \u03c4\u03b9\u03bc\u03ae: \u03b1\u03c0\u03b1\u03b9\u03c4\u03b5\u03af\u03c4\u03b1\u03b9 \u03b1\u03c1\u03b9\u03b8\u03bc\u03cc\u03c2 \u03b3\u03b9\u03b1 \u03c4\u03bf \u03ba\u03c5\u03bc\u03b1\u03b9\u03bd\u03cc\u03bc\u03b5\u03bd\u03bf \u03c3\u03b7\u03bc\u03b5\u03af\u03bf
 UI.dialog.quit                                        = \u0395\u03b3\u03ba\u03b1\u03c4\u03b1\u03bb\u03b5\u03af\u03c8\u03c4\u03b5
 UI.dialog.quit_and_disconnect_msg                     = \n\
 \u0398\u03ad\u03bb\u03b5\u03c4\u03b5 \u03bd\u03b1 \u03b5\u03b3\u03ba\u03b1\u03c4\u03b1\u03bb\u03b5\u03af\u03c8\u03b5\u03c4\u03b5;\n\
diff --git a/data/i18n/praxis_es.properties b/data/i18n/praxis_es.properties
index e433475d2437fb5dfece12682559ad2bcd1d46db..1932acb219d0663ad79da1e40f2524cd82ebd7d7 100644
--- a/data/i18n/praxis_es.properties
+++ b/data/i18n/praxis_es.properties
@@ -136,6 +136,9 @@ UI.dialog.prg_properties.main_label                   = Descripci\u00f3n de {0}
 UI.dialog.prg_properties.parameters                   = Par\u00e1metros:
 UI.dialog.prg_properties.parameters_default           = (y sus valores por defecto)
 UI.dialog.prg_properties.title                        = Propiedades del programa
+UI.dialog.prg_properties.invalid_value                = Valor no v\u00e1lido
+UI.dialog.prg_properties.invalid_integer_value        = Valor no v\u00e1lido: se requiere un n\u00famero entero
+UI.dialog.prg_properties.invalid_float_value          = Valor no v\u00e1lido: se requiere un n\u00famero de coma flotante
 UI.dialog.quit                                        = Salir
 UI.dialog.quit_and_disconnect_msg                     = \n\
 \u00bfDesea salir?\n\