What exactly do you mean by item limit, because I personally think there are 3 types of item limits.
1) Getting an excess of 500 items messes up tribes. This address that issue
2) There is a limit to the amount of objects that can be viewed in the inventory at one time. This is addressed too I believe, you can have like 100 different types of items and the list will work....or at least I think it does.
3) The amount of weapons/objects that can be put in the server. In theory the system could also be used to create more items than tribes allows but that would take more server-side code, although clicentside would stay the same.