There is an important patch for Miranda IM. If you use the ICQ protocol you could lose some messages. The bug is defined as "unknown TLV(19) bug".

To fix this problem, you have to download and replace the file icq.dll in the Miranda folder.

Download icq.dll

It seems that the ICQ protocol has been changed a little bit and that's why only the official ICQ client is working properly. Other clients like Miranda and QIP must be updated. For QIP you just need to download the latest alpha version.