Security Error

Hi,
 I have recently replaced the expired certificates and after enableing the global secirity i receive below error on starting deployment manager. Has any one come across such exception.
I have manually sync'd the nodes and restarted dmgr as a first step to resolve this issue but no luck.

[8/8/08 10:15:44:037 BST] 00000023 DefaultTokenP E   HMGR0149E: An attempt to open a connection to core group DefaultCoreGroup has been rejected. The sending process has a name of cell_name\node_name\<appserver_name> and an IP address of /<xxx.xxx.xxx.xxx>. Global security in the local process is Enabled. Global security in the sending process is Disabled. The received token starts with -18a75d21:113d9e33bec:-80. The exception is com.ibm.websphere.security.auth.WSLoginFailedException: Validation of LTPA token failed due to invalid keys or token type.
        at com.ibm.ws.security.ltpa.LTPAServerObject.validateToken(LTPAServerObject.java:933)
        at com.ibm.ws.security.token.WSCredentialTokenMapper.validateLTPAToken(WSCredentialTokenMapper.java:1274)
        at com.ibm.ws.hamanager.runtime.DefaultTokenProvider.authenticateMember(DefaultTokenProvider.java:214)
        at com.ibm.ws.hamanager.coordinator.impl.DCSPluginImpl.authenticateMember(DCSPluginImpl.java:724)
        at com.ibm.ws.dcs.vri.transportAdapter.rmmImpl.ptpDiscovery.DiscoveryRcv.acceptStream(DiscoveryRcv.java:266)
        at com.ibm.rmm.ptl.tchan.receiver.PacketProcessor.fetchStream(PacketProcessor.java:470)
        at com.ibm.rmm.ptl.tchan.receiver.PacketProcessor.run(PacketProcessor.java:860)