--- a/util-src/encodings.c	Tue Apr 23 19:21:06 2019 +0200
+++ b/util-src/encodings.c	Wed Apr 24 16:16:19 2019 +0200
@@ -299,7 +299,7 @@
 		return 1;
 	}
 
-	prepped_len = usprep_prepare(profile, unprepped, unprepped_len, prepped, 1024, 0, NULL, &err);
+	prepped_len = usprep_prepare(profile, unprepped, unprepped_len, prepped, 1024, USPREP_ALLOW_UNASSIGNED, NULL, &err);
 
 	if(U_FAILURE(err)) {
 		lua_pushnil(L);