I encountered a bug, mining in yiimp pools if you mine different coins but of the same algorithm the pool address and port remain the same, while the username (wallet) and password (c=coin_short_name) need to change.

Well I added like 3 or 4 pool entry all for neoscrypt coins, and when it first start mining it's all ok, but when it automatically switch to the next most profitable coin it "forget" to change username

Maybe a screenshot can explain it better
https://i.imgur.com/U2Hdkhv.png