I am seeing the same problem with these macros:
case=10790
the problem seems to be fairly specific, since I am getting better tooltips on these macros:
#define MACRO_TOOLTIP_ONE		/* comment first */ int nTest;
#define MACRO_TOOLTIP_TWO		int nTest; /* comment last */ 
#define MACRO_TOOLTIP_THREE		int nTest;
#define MACRO_TOOLTIP_FOUR		int nBracket; } /* comment after bracket */
#define MACRO_TOOLTIP_FIVE		/* comment before bracket */ int nBracket; }