diff --git a/src/jrd/IntlUtil.cpp b/src/jrd/IntlUtil.cpp
index 3b2da26e7b..16e2563e1c 100644
--- a/src/jrd/IntlUtil.cpp
+++ b/src/jrd/IntlUtil.cpp
@@ -656,7 +656,7 @@ static void unicodeDestroy(texttype* tt)
 static USHORT unicodeKeyLength(texttype* tt, USHORT len)
 {
 	return tt->texttype_impl->collation->keyLength(
-		len / tt->texttype_impl->cs->charset_min_bytes_per_char * 4);
+		len / tt->texttype_impl->cs->charset_max_bytes_per_char * 4);
 }