Done, thanks! Since these are all defunct, I removed all of the icons from posts/PMs. Though I kept them on profiles, since I don't like completely removing extant data.
Perhaps it wouldn't be a bad idea to even rename that section in the profile. It's not only ICQ, but also other long-dead services. AIM, MSN, YIM, Skype, none of this is active, nor will it be. Entry fields to be enabled for regular text will not delete or disturb the current entries, and members will have more customization options.
For example, instead of YIM, why not have a "Bitcoin address" field.