This may be due to a new Cisco feature in IOS 12.2SF
The offending command is :
vlan dot1q tag native
This command is designed to prevent VLAN hopping. It forces traffic on the native VLAN (Vlan 1) to be tagged and forwarded as part of the trunk. This in turn prevents the LACP-PDU packets from being received as Crossbeam expects them to be untagged. This was discovered when the packet captures showed no traffic coming from the Cisco during negotiation.
To disable this feature, execute the following command on the Cisco device:
no vlan dot1q tag native