diff --git a/openerp/addons/base/module/wizard/base_import_language.py b/openerp/addons/base/module/wizard/base_import_language.py
index f4108094207..0a5cc592651 100644
--- a/openerp/addons/base/module/wizard/base_import_language.py
+++ b/openerp/addons/base/module/wizard/base_import_language.py
@@ -1,11 +1,18 @@
 # -*- coding: utf-8 -*-
 # Part of Odoo. See LICENSE file for full copyright and licensing details.
 
+import os
 import base64
+import logging
 from tempfile import TemporaryFile
 
 from openerp import tools
 from openerp.osv import osv, fields
+from openerp.exceptions import UserError
+from openerp.tools.translate import _
+
+_logger = logging.getLogger(__name__)
+
 
 class base_language_import(osv.osv_memory):
     """ Language Import """
@@ -16,6 +23,7 @@ class base_language_import(osv.osv_memory):
         'name': fields.char('Language Name', required=True),
         'code': fields.char('ISO Code', size=5, help="ISO Language and Country code, e.g. en_US", required=True),
         'data': fields.binary('File', required=True),
+        'filename': fields.char('File Name', required=True),
         'overwrite': fields.boolean('Overwrite Existing Terms',
                                     help="If you enable this option, existing translations (including custom ones) "
                                          "will be overwritten and replaced by those in this file"),
@@ -33,11 +41,12 @@ class base_language_import(osv.osv_memory):
     
             # now we determine the file format
             fileobj.seek(0)
-            first_line = fileobj.readline().strip().replace('"', '').replace(' ', '')
-            fileformat = first_line.endswith("type,name,res_id,src,value") and 'csv' or 'po'
-            fileobj.seek(0)
+            fileformat = os.path.splitext(this.filename)[-1][1:].lower()
     
             tools.trans_load_data(cr, fileobj, fileformat, this.code, lang_name=this.name, context=context)
+        except Exception, e:
+            _logger.exception('File unsuccessfully imported, due to format mismatch.')
+            raise UserError(_('File not imported due to format mismatch or a malformed file. (Valid formats are .csv, .po, .pot)\n\nTechnical Details:\n%s') % tools.ustr(e))
         finally:
             fileobj.close()
         return True
diff --git a/openerp/addons/base/module/wizard/base_import_language_view.xml b/openerp/addons/base/module/wizard/base_import_language_view.xml
index b75ce6225b9..a29ac349675 100644
--- a/openerp/addons/base/module/wizard/base_import_language_view.xml
+++ b/openerp/addons/base/module/wizard/base_import_language_view.xml
@@ -10,7 +10,8 @@
                     <group>
                         <field name="name" placeholder="e.g. English"/>
                         <field name="code" string="Code" placeholder="e.g. en_US"/>
-                        <field name="data"/>
+                        <field name="data" filename="filename"/>
+                        <field name="filename" invisible="1"/>
                         <field name="overwrite"/>
                     </group>
                     <footer>
diff --git a/openerp/tools/translate.py b/openerp/tools/translate.py
index 72c2190fee3..8cebe086bda 100644
--- a/openerp/tools/translate.py
+++ b/openerp/tools/translate.py
@@ -1028,7 +1028,7 @@ def trans_load_data(cr, fileobj, fileformat, lang, lang_name=None, verbose=True,
                     # and we try to find the corresponding
                     # /path/to/xxx/i18n/xxx.pot file.
                     # (Sometimes we have 'i18n_extra' instead of just 'i18n')
-                    addons_module_i18n, _ = os.path.split(fileobj.name)
+                    addons_module_i18n, _ignored = os.path.split(fileobj.name)
                     addons_module, i18n_dir = os.path.split(addons_module_i18n)
                     addons, module = os.path.split(addons_module)
                     pot_handle = misc.file_open(os.path.join(
@@ -1039,7 +1039,7 @@ def trans_load_data(cr, fileobj, fileformat, lang, lang_name=None, verbose=True,
 
         else:
             _logger.info('Bad file format: %s', fileformat)
-            raise Exception(_('Bad file format'))
+            raise Exception(_('Bad file format: %s') % fileformat)
 
         # Read the POT references, and keep them indexed by source string.
         class Target(object):
@@ -1049,7 +1049,7 @@ def trans_load_data(cr, fileobj, fileformat, lang, lang_name=None, verbose=True,
                 self.comments = None
 
         pot_targets = defaultdict(Target)
-        for type, name, res_id, src, _, comments in pot_reader:
+        for type, name, res_id, src, _ignored, comments in pot_reader:
             if type is not None:
                 target = pot_targets[src]
                 target.targets.add((type, name, res_id))