Marked gcc 4.2.1 as expected failure in optional_test_ref

[SVN r47665]

status/explicit-failures-markup.xml

@@ -2494,7 +2494,7 @@ for more information.
             <toolset name="gcc-mingw-3.4.5"/>
             <toolset name="gcc-3.4.2_hpux_pa_risc"/>
             <toolset name="gcc-3.4.6_linux_ia64"/>
-            <toolset name="gcc-4.2.1*"/>
+            <toolset name="gcc-4.2.*"/>
             <toolset name="gcc-4.1.2_sunos_i86pc"/>
                 <note author="Fernando Cacciola" refid="2"/>
         </mark-expected-failures>