Problem with Foreign Key relationships in SAP R/3 4.7

Hi Experts,

I am trying to create a foreign key relationship between 2 transparent tables in SAP R/3 4.7

Table 1:ZAAVNDR (MANDT (pk), VENDORNO (pk), NAME, REGION, COUNTRY (fk)) Foreign Key Table

Table 2: ZAAVNDRREF(MANDT(pk), COUNTRY (pk)) ---Check table

I have added few valid countries in check table but when I am adding some records in foreign key table with invalid countries these records are not being restricted and are still successfully going into the table.

Could any one please help in this.

Thanks in anticipation.

-Amit