Optical should be able to help get you back on real soon.
We have this in place, because we have had people in the past use malicious programs to use other people's proxys for the purpose of getting their hands on multiple accounts, such as for the use of griefing and spam clients. Unfortunately, your proxy had been used by one of these clients and was detected by our filter as being a "compromised account."
Again, we will have Optical get you back on, since you have said that you changed your account's password.