11 Apr
2008
11 Apr
'08
10:50 a.m.
I forgot to add that at least in the example of wu-ftp you can specify the data ports I think.
Also when you say your firewall can only open certain ports what do you mean ? Usually there is a list of default services which can be added to with "custom" services. which you can then use in your rules. The ZyXEL router I used to have here behaved in this way from memory.