diff --git a/src/template/solaris b/src/template/solaris
index 1487149fd07..eae158fae62 100644
--- a/src/template/solaris
+++ b/src/template/solaris
@@ -11,7 +11,7 @@ esac
 
 THREAD_SUPPORT=yes
 NEED_REENTRANT_FUNCS=yes	# 5.6 2003-09-13
-THREAD_CPPFLAGS="-D_POSIX_PTHREAD_SEMANTICS"
+THREAD_CPPFLAGS="-D_REENTRANT -D_POSIX_PTHREAD_SEMANTICS"
 if test "$GCC" != yes 
 then	THREAD_CPPFLAGS="$THREAD_CPPFLAGS -mt"
 fi