diff --git a/servers/slapd/schema_init.c b/servers/slapd/schema_init.c
index 21adadfb8c..7547e7b9d8 100644
--- a/servers/slapd/schema_init.c
+++ b/servers/slapd/schema_init.c
@@ -1307,7 +1307,7 @@ struct syntax_defs_rec syntax_defs[] = {
 		X_BINARY X_NOT_H_R ")",
 		SLAP_SYNTAX_BINARY|SLAP_SYNTAX_BER, berValidate, NULL, NULL},
 	{"( 1.3.6.1.4.1.1466.115.121.1.50 DESC 'Telephone Number' )",
-		0, blobValidate, NULL, NULL},
+		0, IA5StringValidate, NumericStringNormalize, NULL},
 	{"( 1.3.6.1.4.1.1466.115.121.1.51 DESC 'Teletex Terminal Identifier' )",
 		0, NULL, NULL, NULL},
 	{"( 1.3.6.1.4.1.1466.115.121.1.52 DESC 'Telex Number' )",