diff --git a/test/lexical_cast_inf_nan_test.cpp b/test/lexical_cast_inf_nan_test.cpp
index bb4331a..af1caa0 100755
--- a/test/lexical_cast_inf_nan_test.cpp
+++ b/test/lexical_cast_inf_nan_test.cpp
@@ -85,6 +85,12 @@ void test_inf_nan_templated()
     BOOST_CHECK( is_pos_inf( lexical_cast<test_t>("+infinity") ) );
     BOOST_CHECK( is_pos_inf( lexical_cast<test_t>("+INFINITY") ) );
 
+    BOOST_CHECK( is_pos_inf( lexical_cast<test_t>("iNfiNity") ) );
+    BOOST_CHECK( is_pos_inf( lexical_cast<test_t>("INfinity") ) );
+
+    BOOST_CHECK( is_neg_inf( lexical_cast<test_t>("-inFINITY") ) );
+    BOOST_CHECK( is_neg_inf( lexical_cast<test_t>("-INFINITY") ) );
+
     BOOST_CHECK( is_pos_nan( lexical_cast<test_t>("nan") ) );
     BOOST_CHECK( is_pos_nan( lexical_cast<test_t>("NAN") ) );
 
@@ -94,6 +100,15 @@ void test_inf_nan_templated()
     BOOST_CHECK( is_pos_nan( lexical_cast<test_t>("+nan") ) );
     BOOST_CHECK( is_pos_nan( lexical_cast<test_t>("+NAN") ) );
 
+    BOOST_CHECK( is_pos_nan( lexical_cast<test_t>("nAn") ) );
+    BOOST_CHECK( is_pos_nan( lexical_cast<test_t>("NaN") ) );
+
+    BOOST_CHECK( is_neg_nan( lexical_cast<test_t>("-nAn") ) );
+    BOOST_CHECK( is_neg_nan( lexical_cast<test_t>("-NaN") ) );
+
+    BOOST_CHECK( is_pos_nan( lexical_cast<test_t>("+Nan") ) );
+    BOOST_CHECK( is_pos_nan( lexical_cast<test_t>("+nAN") ) );
+
     BOOST_CHECK( is_pos_nan( lexical_cast<test_t>("nan()") ) );
     BOOST_CHECK( is_pos_nan( lexical_cast<test_t>("NAN(some string)") ) );
     BOOST_CHECK_THROW( lexical_cast<test_t>("NAN(some string"), bad_lexical_cast );
@@ -127,6 +142,12 @@ void test_inf_nan_templated()
     BOOST_CHECK( is_pos_inf( lexical_cast<test_t>(L"+infinity") ) );
     BOOST_CHECK( is_pos_inf( lexical_cast<test_t>(L"+INFINITY") ) );
 
+    BOOST_CHECK( is_neg_inf( lexical_cast<test_t>(L"-infINIty") ) );
+    BOOST_CHECK( is_neg_inf( lexical_cast<test_t>(L"-INFiniTY") ) );
+
+    BOOST_CHECK( is_pos_inf( lexical_cast<test_t>(L"+inFINIty") ) );
+    BOOST_CHECK( is_pos_inf( lexical_cast<test_t>(L"+INfinITY") ) );
+
     BOOST_CHECK( is_pos_nan( lexical_cast<test_t>(L"nan") ) );
     BOOST_CHECK( is_pos_nan( lexical_cast<test_t>(L"NAN") ) );