--- a/sdi/models.py	Sat May 29 10:35:45 2010 +0530
+++ b/sdi/models.py	Sat May 29 11:41:52 2010 +0530
@@ -37,7 +37,7 @@
     profession = models.CharField(max_length=20)
     affiliated_to = models.CharField(max_length=30)
 
-    topics_interested = models.CharField(max_length=30)
+    topics_interested = models.CharField(max_length=30, blank=True)
 
     knowledge_of_python = models.CharField(max_length=1, choices=PYTHON_KNOWLEDGE_CHOICES)
     need_for_python_workshop = models.BooleanField(verbose_name="Do you need a workshop on Python before you attend Sage Days")