thats simple...
Official server CLIENT is uppdated .... and adjusted to work with more then 999 lookfaces and ability to catch properly effects on mounts. Official client is updated with sets of new codes that will do even more....
And since old one is not... you wont be able to change just via ollydbg etc... you would need to have source files to code new stuff OR attached properly coded files to work under certain parts of client ...
In other words... if you are not High programmer and dont know Very well how to do this ... then dont think about it

I as myself dont even focus on this ... not worth currently fight for these parts ...
I suggest you to focus on parts that can be done... as believe me ... its more then you cannot