3750 mac-address-aging timer

Hi,
i'm trying to change mac-address timers but having problems, i.e the change I’m trying to change mac-address-aging timers but having problems, i.e. the change only applies to existing active vlans. if i add new vlan after changing mac-address-aging timer it will have default value 300. Is this way it works or I’m missing something?
3750-sw-1(config)#mac-ad aging-time 1300
3750-sw-1#sh mac-ad ag
Vlan Aging Time
10 1300
20 1300
30 1300
3750-sw-1#! Now adding a new vlan
3750-sw-1#conf t
3750-sw-1(config)#vlan 40
3750-sw-1 (config-vlan
3750-sw-1#sh mac-ad ag
Vlan Aging Time
10 1300
20 1300
30 1300
40 300
New vlan 40 has default value????

Just checked the command reference. In the usage guidelines it states:
Usage Guidelines
If hosts do not send continuously, increase the aging time to record the dynamic entries for a longer time. Increasing the time can reduce the possibility of flooding when the hosts send again.
If you do not specify a specific VLAN, this command sets the aging time for all VLANs.
The last sentence is relevant to your question. The command may also be issued on a particular vlan.
New vlans are created after setting this parameter globally will hence be using the default values.
The key issue to check if this is a bug or not is to check whether the global command is reflected in the config. If it was, I would call the issue a bug.
As it is not, you must approach this as a parameter that can (and should) be set per vlan. After creating a new vlan, you may add this line in the script or re-issue the global command.
Regards,
Leo

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