diff --git a/libraries/liblutil/setproctitle.c b/libraries/liblutil/setproctitle.c
index 8c5ed0700c..b2a590b612 100644
--- a/libraries/liblutil/setproctitle.c
+++ b/libraries/liblutil/setproctitle.c
@@ -54,8 +54,15 @@ va_dcl
 	va_start(ap);
 #endif
 
+#ifdef HAVE_VSNPRINTF
 	buf[sizeof(buf) - 1] = '\0';
 	vsnprintf( buf, sizeof(buf)-1, fmt, ap );
+#elif HAVE_VPRINTF
+	vsprintf( buf, fmt, ap ); /* hope it's not too long */
+#else
+	/* use doprnt() */
+	chokeme = "choke me!  I don't have a doprnt() manual handy";
+#endif
 
 	va_end(ap);