diff --git a/test/bug.calc.t b/test/bug.calc.t
new file mode 100755
index 000000000..9c2ed36e8
--- /dev/null
+++ b/test/bug.calc.t
@@ -0,0 +1,41 @@
+#! /usr/bin/env perl
+################################################################################
+##
+## Copyright 2006 - 2014, Paul Beckingham, Federico Hernandez.
+##
+## Permission is hereby granted, free of charge, to any person obtaining a copy
+## of this software and associated documentation files (the "Software"), to deal
+## in the Software without restriction, including without limitation the rights
+## to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+## copies of the Software, and to permit persons to whom the Software is
+## furnished to do so, subject to the following conditions:
+##
+## The above copyright notice and this permission notice shall be included
+## in all copies or substantial portions of the Software.
+##
+## THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+## OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+## FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+## THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+## LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+## OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+## SOFTWARE.
+##
+## http://www.opensource.org/licenses/mit-license.php
+##
+################################################################################
+
+use strict;
+use warnings;
+use Test::More tests => 5;
+
+# '15min' is seen as '15', 'min', not '15min' duration.
+my $output = qx{../src/calc --debug 15min};
+unlike ($output, qr/token infix '15' Date/,           'Misinterpretation: 15min -> 15');
+unlike ($output, qr/token infix 'min' Identifier/,    'Misinterpretation: 15min -> m');
+unlike ($output, qr/Error: Unexpected stack size: 2/, 'Unexpected stack size');
+like ($output, qr/\[1\] eval push '15min' Duration/,  '15min -> 15min Duration');
+like ($output, qr/PT15M/,                             '15min -> PT15m Duration');
+
+exit 0;
+