Question : ZONE replication in DNS..

Hi,
I have 6 DNS servers in my infrastrcture however they have all zones as AD integerated but few zones are customized. now when i set zone replication for those customized zones it did'nt works.
Please help me on this and let me know the correct way to confirure it.
All DNS servers are running on Microsoft WIndows server 2003 standard/enterprise and 2008 as well.

Answer : ZONE replication in DNS..

Did you made any changes on the GAL?
if yes you might need to wait for replication.