That should be easy.
Or u can use an alias that contains CRC.
Then you should enforce using CRCed aliases only.
It's a client soft issue.
This solution is ugly.
1) You will have aliases like CfB\0CFA67D9 - looks ugly
2) In another client your alias will be just CfB => people will get confused what your alias really is.
3) Some people won't use aliases at all and will continue to send money to nowhere.
It's a total mess.