This patch make ZNC query buffering behave the way I like, as I use
multiple clients and still want the query buffer to be filled and replayed
for the newly connecting client.

diff -rup znc-0.074/IRCSock.cpp znc/IRCSock.cpp
--- znc-0.074/IRCSock.cpp	2009-06-29 13:26:19 +0200
+++ znc/IRCSock.cpp	2009-08-26 11:30:56 +0200
@@ -724,21 +724,14 @@ bool CIRCSock::OnGeneralCTCP(CNick& Nick
 bool CIRCSock::OnPrivNotice(CNick& Nick, CString& sMessage) {
 	MODULECALL(OnPrivNotice(Nick, sMessage), m_pUser, NULL, return true);
 
-	if (!m_pUser->IsUserAttached()) {
-		// If the user is detached, add to the buffer
-		m_pUser->AddQueryBuffer(":" + Nick.GetNickMask() + " NOTICE ", " :" + m_pUser->AddTimestamp(sMessage));
-	}
+	m_pUser->AddQueryBuffer(":" + Nick.GetNickMask() + " NOTICE ", " :" + m_pUser->AddTimestamp(sMessage));
 
 	return false;
 }
 
 bool CIRCSock::OnPrivMsg(CNick& Nick, CString& sMessage) {
 	MODULECALL(OnPrivMsg(Nick, sMessage), m_pUser, NULL, return true);
-
-	if (!m_pUser->IsUserAttached()) {
-		// If the user is detached, add to the buffer
-		m_pUser->AddQueryBuffer(":" + Nick.GetNickMask() + " PRIVMSG ", " :" + m_pUser->AddTimestamp(sMessage));
-	}
+	m_pUser->AddQueryBuffer(":" + Nick.GetNickMask() + " PRIVMSG ", " :" + m_pUser->AddTimestamp(sMessage));
 
 	return false;
 }
diff -rup znc-0.074/User.cpp znc/User.cpp
--- znc-0.074/User.cpp	2009-07-22 18:54:52 +0200
+++ znc/User.cpp	2009-08-26 11:30:56 +0200
@@ -290,6 +290,7 @@ void CUser::UserConnected(CClient* pClie
 		MODULECALL(OnPrivBufferPlayLine(*pClient, sBufLine), this, NULL, continue);
 		pClient->PutClient(sBufLine);
 	}
+	m_QueryBuffer.Clear();
 
 	// Tell them why they won't connect
 	if (!GetIRCConnectEnabled())