diff --git a/weboob/applications/boobank/boobank.py b/weboob/applications/boobank/boobank.py
index d7cbb01e..18012bed 100644
--- a/weboob/applications/boobank/boobank.py
+++ b/weboob/applications/boobank/boobank.py
@@ -42,8 +42,9 @@ class QifFormatter(IFormatter):
             result += u'!type:Bank\n'
         result += u'D%s\n' % item['date'].strftime('%d/%m/%y')
         result += u'T%s\n' % item['amount']
+        if item['category']:
+            result += u'N%s\n' % item['category']
         result += u'M%s\n' % item['label']
-        result += u'N%s\n' % item['category']
         result += u'^\n'
         self.count += 1
         return result
diff --git a/weboob/capabilities/bank.py b/weboob/capabilities/bank.py
index e98a25ec..e4347fca 100644
--- a/weboob/capabilities/bank.py
+++ b/weboob/capabilities/bank.py
@@ -57,9 +57,9 @@ class Operation(CapBaseObject):
     def __init__(self, id):
         CapBaseObject.__init__(self, id)
         self.add_field('date', (basestring, datetime, date))
+        self.add_field('category', unicode)
         self.add_field('label', unicode)
         self.add_field('amount', float)
-        self.add_field('category', unicode)
 
     def __repr__(self):
         return "<Operation date='%s' label='%s' amount=%s>" % (self.date,