Index: trunk/resources/data/validator/numeric.mapcss
===================================================================
--- trunk/resources/data/validator/numeric.mapcss	(revision 16006)
+++ trunk/resources/data/validator/numeric.mapcss	(revision 16316)
@@ -254,4 +254,6 @@
 
 /* must be an integer positive number only and not 0, see #10837 (lanes), #11055 (screen) */
+node[seats][seats !~ /^[1-9]([0-9]*)$/][amenity=bench],
+way[seats][seats !~ /^[1-9]([0-9]*)$/][amenity=bench],
 way[lanes][lanes !~ /^[1-9]([0-9]*)$/][highway],
 way["lanes:backward"]["lanes:backward" !~ /^[1-9]([0-9]*)$/][highway],