Core issue
This message means one or more secure VLANs belong to both secured and ordinary trunks. This configuration may create security holes in secure VLANs.
This is a simple warning message and cosmetic in nature. It tells you that you have trunked VLANs defined in a firewall vlan-group. This happens when you are running failover across modules.
This message was designed in the very early phases of the FWSM development.
Resolution
Change the trunk or the secure VLAN configuration so that they do not overlap.
Enter either the switchport trunk allowed vlan command to change the trunk configuration or the firewall vlan-group command to change the secure VLAN configuration.
For more information, refer to Configuring the Switch for the Firewall Services Module