diff --git a/src/build/feature.py b/src/build/feature.py
index 2ab6e5c67..386e49931 100644
--- a/src/build/feature.py
+++ b/src/build/feature.py
@@ -442,7 +442,7 @@ def validate_value_string (f, value_string):
     # An empty value is allowed for optional features
     if not values[0] in f.values() and \
            (values[0] or not f.optional()):
-        raise InvalidValue ("'%s' is not a known value of feature '%s'\nlegal values: '%s'" % (values [0], feature, f.values()))
+        raise InvalidValue ("'%s' is not a known value of feature '%s'\nlegal values: '%s'" % (values [0], f.name(), f.values()))
 
     for v in values [1:]:
         # this will validate any subfeature values in value-string