Change Sysmaster IP address

Hello,

I am running a Sysmaster and need to change the Public IP address it is on. I have changed the IP address in the Administrative Console – Navigator -> Network Management -> Server Configuration and then IP address configuration. It shows the new IP addresses every but yet the server will not adopt the new address (it keeps the old one and this is shown in the front LCD too). Does anyone know what else need sto be changed and there is nothing in the config documents.