How do I connect two Cisco Catalyst 2950 over LAN?

I'm trying to connect (2) Cisco Catalyst 2950's over each's respective FastEthernet 0/1 ports, but for some reason, they're not communicating. I'm doing this to physically extend my network and add more network ports.

On SwitchA (10.10.10.1) I have:

!
interface Porth-Channel1
 description UPLINK
 switchport mode trunk
 switchport nonegotiate
 flowcontrol send off
end
!
interface FastEthernet0/1
 description ETHERNET-UPLINK
 switchport mode trunk
 channel-group 1 mode active
end

On SwitchB (10.10.10.2) I have:

!
interface Porth-Channel1
 description UPLINK
 switchport mode trunk
 switchport nonegotiate
 flowcontrol send off
end
!
interface FastEthernet0/1
 description ETHERNET-UPLINK
 switchport mode trunk
 channel-group 1 mode active
end

I have the same config set up on an 8-port 2960 (SwitchC), and if I plug FastEthernet 0/1 of SwitchC to SwitchB or SwitchA, it works. But if I plug FastEthernet 0/1 of SwitchB to SwitchA, it doesn't work.

Am I missing something? How do I get it so I can connect 2 Cisco 2950 switches together?

UPDATE 1

On SwitchA:

#show int port-channel 1 trunk

Port        Mode         Encapsulation  Status        Native vlan
Po1         on           802.1q         trunking      1

Port      Vlans allowed on trunk
Po1         1-4094

Port        Vlans allowed and active in management domain
Po1         1-2,5,30,112,115,120

Port        Vlans in spanning tree forwarding state and not pruned
Po1         1-2,5,30,112,115,120

On SwitchB:

#show int port-channel 1 trunk

Port        Mode         Encapsulation  Status        Native vlan
Po1         on           802.1q         trunking      1

Port      Vlans allowed on trunk
Po1         none

Port        Vlans allowed and active in management domain
Po1         none

Port        Vlans in spanning tree forwarding state and not pruned
Po1         none

For SwitchB, I've tried to add all vlans to be allowed, but it doesn't change anything:

#config t
#int port-channel 1
#switchport trunk allowed vlan all

I've also tried:

#switchport trunk allowed vlan 1-4094

But the allowed vlan's doesn't change to what I tell it to. How do I fix this?

UPDATE 2

I ran a show int po1 switchport on both switches:

SwitchA

#show int po1 switchport
Name: Po1
Switchport: Enabled
Administrative Mode: trunk
Operational Mode: trunk
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: dot1q
Negotiation of Trunking: Off
Access Mode VLAN: 1 (default)
Trunking Native Mode VLAN: 1 (default)
Voice VLAN: none
Administrative private-vlan host-association: none
Administrative private-vlan mapping: none
Administrative private-vlan trunk native VLAN: none
Administrative private-vlan trunk encapsulation: dot1q
Administrative private-vlan trunk normal VLANs: none
Administrative private-vlan trunk private VLANs: none
Operational private-vlan: none
Trunking VLANs Enabled: ALL
Pruning VLANs Enabled: 2-1001
Protected: false

Appliance trust: none

SwitchB

#show int po1 switchport
Name: Po1
Switchport: Enabled
Administrative Mode: trunk
Operational Mode: down
Administrative Trunking Encapsulation: dot1q
Negotiation of Trunking: Off
Access Mode VLAN: 1 (default)
Trunking Native Mode VLAN: 1 (default)
Voice VLAN: none
Administrative private-vlan host-association: none
Administrative private-vlan mapping: none
Administrative private-vlan trunk native VLAN: none
Administrative private-vlan trunk encapsulation: dot1q
Administrative private-vlan trunk normal VLANs: none
Administrative private-vlan trunk private VLANs: none
Operational private-vlan: none
Trunking VLANs Enabled: ALL
Pruning VLANs Enabled: 2-1001
Protected: false

Appliance trust: none

Still no clue as to why show int po1 trunk shows Vlans allowed on trunk: none