diff --git a/dkim/__init__.py b/dkim/__init__.py
index dbcfa8d..7b9a663 100644
--- a/dkim/__init__.py
+++ b/dkim/__init__.py
@@ -591,13 +591,13 @@ def sign(message, selector, domain, privkey, identity=None,
         include_headers = d.all_sign_headers()
     return d.sign(selector, domain, privkey, identity=identity, canonicalize=canonicalize, include_headers=include_headers, length=length)
 
-def verify(message, logger=None, dnsfunc=get_txt):
+def verify(message, logger=None, dnsfunc=get_txt, minkey=1024):
     """Verify the first (topmost) DKIM signature on an RFC822 formatted message.
     @param message: an RFC822 formatted message (with either \\n or \\r\\n line endings)
     @param logger: a logger to which debug info will be written (default None)
     @return: True if signature verifies or False otherwise
     """
-    d = DKIM(message,logger=logger)
+    d = DKIM(message,logger=logger,minkey=minkey)
     try:
         return d.verify(dnsfunc=dnsfunc)
     except DKIMException as x:
diff --git a/dkim/tests/test_dkim.py b/dkim/tests/test_dkim.py
index 5805bf2..ed18ce1 100644
--- a/dkim/tests/test_dkim.py
+++ b/dkim/tests/test_dkim.py
@@ -135,7 +135,15 @@ b/mPfjC0QJTocVBq6Za/PlzfV+Py92VaCak19F4WrbVTK5Gg5tW220MCAwEAAQ=="""
         # simple canonicalization.  
         # http://tools.ietf.org/html/rfc4871#section-3.5
         signed = dkim.fold(dkim_header) + sample_msg
-        result = dkim.verify(signed,dnsfunc=lambda x: _dns_responses[x])
+        result = dkim.verify(signed,dnsfunc=lambda x: _dns_responses[x],
+                minkey=512)
+        self.assertTrue(result)
+        dkim_header = dkim.fold(dkim_header)
+        # use a tab for last fold to test tab in FWS bug
+        pos = dkim_header.rindex(b'\r\n ')
+        dkim_header = dkim_header[:pos]+b'\r\n\t'+dkim_header[pos+3:]
+        result = dkim.verify(dkim_header + sample_msg,
+                dnsfunc=lambda x: _dns_responses[x], minkey=512)
         self.assertTrue(result)
 
     def test_extra_headers(self):