Test for __sun instead of __sun__, since SUNWspro only defines the latter;
gcc defines both.
diff --git a/Modules/_cursesmodule.c b/Modules/_cursesmodule.c
index a56a67c..6f79aa0 100644
--- a/Modules/_cursesmodule.c
+++ b/Modules/_cursesmodule.c
@@ -118,7 +118,7 @@
 #include <term.h>
 #endif
 
-#if defined(sgi) || defined(__sun__)
+#if defined(sgi) || defined(__sun)
 #define STRICT_SYSV_CURSES       /* Don't use ncurses extensions */
 typedef chtype attr_t;           /* No attr_t type is available */
 #endif