Packet decryption problem..

In Lowfyr's packet decryption guide, first step to get key3/key4

1.) Add key 1 with key 2 205C48F4 + 0044A62E = 20A0EF22

What do I do when key1+key2 is more than 4 bytes? Discard the first byte?
Just as an example, I have gotten this from the server..
key1 363504E3 key2 D9007F2D
add them together = 10F358410
do I just discard the 1 and end up with 0F358410?

(edit, 4 bytes not 8, as you can probably tell i am very good with making mistakes)

That shouldn't ever happen.

Key2 is your AccountID. They're based on a counter, where each new account ID is counter+1. ATM, there's about 7 million accounts, but its unlikely it'll ever get higher.

Key1 is always under 1 billion.

Hmm.. yeah, I may have made an error with that packet (I got it once, then copied it manually to decrypt as a test...) other packets seem to have keys the right size. thanks.

edit: actually... Ultima's advice in the thread is wrong.. the keys' location haven't moved from when the packet was 28bytes from what I can see... :?