This question was asked already, not in the same wording, but it has been asked.
i'll explain that by searching through past postings, you will find a solution to your question.
You don't say which version, so i will guess it was icq99 or 98, you may be able to get it to work - doubtful though, and if you DID, your staying with the older version will be a pain, and you will never receive your offline messages, so you will then be losing a big part of the icq program, which is the ability to send and recevie offline messages.
You have to upgrade, to atleast a version which uses the ver. 8 protocol if you want to use the program as intended. if you like backing up your icq contact list and never getting offline replies from people, then go ahead and see if you can run a v5 protocol client.
anyway, what do you mean by them forcing you to upgrade? if your using icq98/99, then your holding on to a relic which really serves you no good. You should have have mentioned which version your trying to continue to use, even if someone did have a solution to your question, you never said which one you want to keep on life-support.
you generally have to use what they want you to use, since the servers which you connect to run on a modern protocol and will refuse those old old clients from connecting, as they are security risks to you and them, so they will not permit you to connect.
also with the OSCAR protocol version, you get the benefit of server-side contact lists. which then permit you the ability to use web-based icq clients.
if your referring to being forced to upgrade to icq2003b, you dont have to do that. you can continue to use icq2003a if you like. - but you never said which one you'd like. So i can only guess.