diff --git a/fdroidserver/exception.py b/fdroidserver/exception.py
index 4a3570d2..51481c56 100644
--- a/fdroidserver/exception.py
+++ b/fdroidserver/exception.py
@@ -17,7 +17,10 @@ class FDroidException(Exception):
         return ret
 
     def __str__(self):
-        ret = self.value
+        if self.value is None:
+            ret = __name__
+        else:
+            ret = str(self.value)
         if self.detail:
             ret += "\n==== detail begin ====\n%s\n==== detail end ====" % ''.join(self.detail).strip()
         return ret
diff --git a/tests/exception.TestCase b/tests/exception.TestCase
new file mode 100755
index 00000000..01d0a5af
--- /dev/null
+++ b/tests/exception.TestCase
@@ -0,0 +1,65 @@
+#!/usr/bin/env python3
+
+# http://www.drdobbs.com/testing/unit-testing-with-python/240165163
+
+import inspect
+import optparse
+import os
+import sys
+import unittest
+
+localmodule = os.path.realpath(
+    os.path.join(os.path.dirname(inspect.getfile(inspect.currentframe())), '..'))
+print('localmodule: ' + localmodule)
+if localmodule not in sys.path:
+    sys.path.insert(0, localmodule)
+
+import fdroidserver.common
+import fdroidserver.exception
+
+
+class ExceptionTest(unittest.TestCase):
+    '''fdroidserver/exception.py'''
+
+    def test_FDroidException(self):
+        try:
+            raise fdroidserver.exception.FDroidException()
+        except fdroidserver.exception.FDroidException as e:
+            str(e)
+
+        try:
+            raise fdroidserver.exception.FDroidException(9)
+        except fdroidserver.exception.FDroidException as e:
+            str(e)
+
+        try:
+            raise fdroidserver.exception.FDroidException(-123.12234)
+        except fdroidserver.exception.FDroidException as e:
+            str(e)
+
+        try:
+            raise fdroidserver.exception.FDroidException("this is a string")
+        except fdroidserver.exception.FDroidException as e:
+            str(e)
+
+        try:
+            raise fdroidserver.exception.FDroidException(['one', 'two', 'three'])
+        except fdroidserver.exception.FDroidException as e:
+            str(e)
+
+        try:
+            raise fdroidserver.exception.FDroidException(('one', 'two', 'three'))
+        except fdroidserver.exception.FDroidException as e:
+            str(e)
+
+
+if __name__ == "__main__":
+    parser = optparse.OptionParser()
+    parser.add_option("-v", "--verbose", action="store_true", default=False,
+                      help="Spew out even more information than normal")
+    (fdroidserver.exception.options, args) = parser.parse_args(['--verbose'])
+    fdroidserver.common.options = fdroidserver.exception.options
+
+    newSuite = unittest.TestSuite()
+    newSuite.addTest(unittest.makeSuite(ExceptionTest))
+    unittest.main()