1 files changed, 2 insertions, 2 deletions
diff --git a/stdnum/si/ddv.py b/stdnum/si/ddv.py
index 5b16dbc..bb6d986 100644
--- a/stdnum/si/ddv.py
+++ b/stdnum/si/ddv.py
@@ -33,7 +33,7 @@ InvalidChecksum: ...
 """
 
 from stdnum.exceptions import *
-from stdnum.util import clean
+from stdnum.util import clean, isdigits
 
 
 def compact(number):
@@ -57,7 +57,7 @@ def validate(number):
     """Check if the number is a valid VAT number. This checks the length,
     formatting and check digit."""
     number = compact(number)
-    if not number.isdigit() or number.startswith('0'):
+    if not isdigits(number) or number.startswith('0'):
         raise InvalidFormat()
     if len(number) != 8:
         raise InvalidLength()