diff --git a/src/commands.py b/src/commands.py
index ef3d2c043..7747589a8 100644
--- a/src/commands.py
+++ b/src/commands.py
@@ -1,6 +1,6 @@
 ###
 # Copyright (c) 2002-2005, Jeremiah Fincher
-# Copyright (c) 2009-2010, James McCoy
+# Copyright (c) 2009-2010,2015, James McCoy
 # All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
@@ -375,8 +375,8 @@ def _getRe(f):
                 else:
                     state.args.append(s)
             else:
-                state.errorInvalid('regular expression', s)
-        except IndexError:
+                raise ValueError
+        except (ValueError, IndexError):
             args[:] = original
             state.errorInvalid('regular expression', s)
     return get
diff --git a/test/test_commands.py b/test/test_commands.py
index 31c9a04fc..cc94c8c1f 100644
--- a/test/test_commands.py
+++ b/test/test_commands.py
@@ -1,5 +1,6 @@
 ###
 # Copyright (c) 2002-2005, Jeremiah Fincher
+# Copyright (c) 2015, James McCoy
 # All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
@@ -181,5 +182,9 @@ class FirstTestCase(CommandsTestCase):
         self.assertStateErrored([first('int', 'something')], ['words'],
                                 errored=False)
 
+    def testLongRegexp(self):
+        spec = [first('regexpMatcher', 'regexpReplacer'), 'text']
+        self.assertStateErrored(spec, ['s/foo/bar/', 'x' * 512], errored=False)
+
 # vim:set shiftwidth=4 softtabstop=4 expandtab textwidth=79: