--- loncom/homework/grades.pm	2005/08/30 14:52:51	1.281
+++ loncom/homework/grades.pm	2005/09/01 15:23:23	1.282
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # The LON-CAPA Grading handler
 #
-# $Id: grades.pm,v 1.281 2005/08/30 14:52:51 albertel Exp $
+# $Id: grades.pm,v 1.282 2005/09/01 15:23:23 www Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -471,6 +471,10 @@ sub most_similar {
 
     $uessay=~s/\W+/ /gs;
 
+# ignore empty submissions (occuring when only files are sent)
+
+    unless ($uessay=~/\w+/) { return ''; }
+
 # these will be returned. Do not care if not at least 50 percent similar
     my $limit=0.6;
     my $sname='';