PowerConnect 5548: incorrect VLAN trunk configuration when loading config

Firmware version: 4.1.0.8.

This is how to reproduce the problem:

1) configure 802.1q trunk with native VLAN other then 1, for example:

interface gigabitethernet1/0/1
 switchport mode trunk
 switchport trunk native vlan 30
 switchport trunk allowed vlan add 30,101

2) save switch config on TFTP server or locally via HTTP

in the saved file VLAN configuration on interface looks like this:

interface gigabitethernet1/0/1
 switchport mode trunk
 switchport trunk native vlan 30
 switchport trunk allowed vlan remove 1-29,31-100,102-4094

3) load saved configuration as startup-config

check loaded config ('more  startup-config'):

interface gigabitethernet1/0/1
 switchport mode trunk
 switchport trunk native vlan 30
 switchport trunk allowed vlan none

As a result interface is not operational.

If you edit saved file like this:

 interface gigabitethernet1/0/1
  switchport mode trunk
  switchport trunk native vlan 30
- switchport trunk allowed vlan remove 1-29,31-100,102-4094
+ switchport trunk allowed vlan add 30,101

configuration is loaded correctly.

This looks like not completely fixed bug from 4.1.0.1 when you were getting 'allowed vlan none' also in case of native vlan 1.