Index: boost/config/platform/linux.hpp
===================================================================
--- boost/config/platform/linux.hpp	(revision 57877)
+++ boost/config/platform/linux.hpp	(working copy)
@@ -40,6 +40,11 @@
 #    define BOOST_NO_SWPRINTF
 #  endif
 
+   // Comeau C++ (como) on linux does not have C99 functions
+   // (used in test, program_options)
+#  define BOOST_NO_SNPRINTF
+#  define BOOST_NO_VSNPRINTF
+
 #endif
 
 //
Index: boost/test/impl/execution_monitor.ipp
===================================================================
--- boost/test/impl/execution_monitor.ipp	(revision 57877)
+++ boost/test/impl/execution_monitor.ipp	(working copy)
@@ -198,6 +198,10 @@
 #include <errno.h>
 #endif
 
+#if defined(BOOST_NO_VSNPRINTF)
+using ::boost::unit_test::ut_detail::vsnprintf;
+#endif
+
 #include <boost/test/detail/suppress_warnings.hpp>
 
 //____________________________________________________________________________//
Index: boost/test/impl/debug.ipp
===================================================================
--- boost/test/impl/debug.ipp	(revision 57877)
+++ boost/test/impl/debug.ipp	(working copy)
@@ -108,6 +108,10 @@
 
 #endif
 
+#if defined(BOOST_NO_SNPRINTF)
+using ::boost::unit_test::ut_detail::snprintf;
+#endif
+
 #include <boost/test/detail/suppress_warnings.hpp>
 
 //____________________________________________________________________________//
Index: boost/test/detail/workaround.hpp
===================================================================
--- boost/test/detail/workaround.hpp	(revision 57877)
+++ boost/test/detail/workaround.hpp	(working copy)
@@ -20,7 +20,7 @@
 
 // STL
 #include <iterator>     // for std::distance
-
+#include <cstdio>       // for sprintf, vsprintf
 #include <boost/test/detail/suppress_warnings.hpp>
 
 //____________________________________________________________________________//
@@ -48,6 +48,31 @@
 using std::distance;
 #endif
 
+// snprintf, vsnprintf workaround for Comeau C/C++ toolset
+#if defined(__COMO__) 
+
+#  if defined(BOOST_NO_SNPRINTF)
+int snprintf(char *s, size_t /*maxlen*/, const char *format, ...)
+{
+    va_list arg;
+    int retval;
+    va_start(arg, format);
+    retval = std::vsprintf(s, format, arg);
+    va_end(arg);
+    return retval;
+}
+#  endif
+
+#  if defined(BOOST_NO_VSNPRINTF)
+int vsnprintf(char *s, size_t maxlen, const char *format, va_list arg)
+{
+    return std::vsprintf(s, format, arg);
+}
+#  endif
+
+#endif
+
+
 template <class T> inline void ignore_unused_variable_warning(const T&) {}
 
 } // namespace ut_detail