diff --git a/include/znc/Utils.h b/include/znc/Utils.h
index 88a88ab6..e37dbff6 100644
--- a/include/znc/Utils.h
+++ b/include/znc/Utils.h
@@ -73,6 +73,9 @@ public:
 	static void GenerateCert(FILE *pOut, const CString& sHost = "");
 #endif /* HAVE_LIBSSL */
 
+	static CString CTime(time_t t, const CString& sTZ);
+	static CString FormatTime(time_t t, const CString& sFormat, const CString& sTZ);
+
 private:
 protected:
 };
diff --git a/modules/extra/listsockets.cpp b/modules/extra/listsockets.cpp
index 625c6ccd..f7c1330f 100644
--- a/modules/extra/listsockets.cpp
+++ b/modules/extra/listsockets.cpp
@@ -155,7 +155,7 @@ public:
 	CString GetCreatedTime(Csock* pSocket) {
 		unsigned long long iStartTime = pSocket->GetStartTime();
 		time_t iTime = iStartTime / 1000;
-		return FormatTime("%Y-%m-%d %H:%M:%S", iTime);
+		return CUtils::FormatTime(iTime, "%Y-%m-%d %H:%M:%S", m_pUser->GetTimezone());
 	}
 
 	CString GetLocalHost(Csock* pSocket, bool bShowHosts) {
@@ -241,19 +241,6 @@ public:
 	virtual ~CListSockets() {
 	}
 
-	CString FormatTime(const CString& sFormat, time_t tm = 0) const {
-		char szTimestamp[1024];
-
-		if (tm == 0) {
-			tm = time(NULL);
-		}
-
-		setenv("TZ", m_pUser->GetTimezone().c_str(), 1);
-		strftime(szTimestamp, sizeof(szTimestamp) / sizeof(char),
-				sFormat.c_str(), localtime(&tm));
-
-		return szTimestamp;
-	}
 };
 
 MODULEDEFS(CListSockets, "List active sockets")
diff --git a/modules/log.cpp b/modules/log.cpp
index 73061484..793002d7 100644
--- a/modules/log.cpp
+++ b/modules/log.cpp
@@ -58,21 +58,15 @@ void CLogMod::PutLog(const CString& sLine, const CString& sWindow /*= "Status"*/
 {
 	CString sPath;
 	time_t curtime;
-	tm* timeinfo;
-	char buffer[1024];
 
 	time(&curtime);
-	// Don't forget the user's timezone offset
-	setenv("TZ", m_pUser->GetTimezone().c_str(), 1);
-	timeinfo = localtime(&curtime);
-
 	// Generate file name
-	if (!strftime(buffer, sizeof(buffer), m_sLogPath.c_str(), timeinfo))
+	sPath = CUtils::FormatTime(curtime, m_sLogPath, m_pUser->GetTimezone());
+	if (sPath.empty())
 	{
 		DEBUG("Could not format log path [" << sPath << "]");
 		return;
 	}
-	sPath = buffer;
 
 	// $WINDOW has to be handled last, since it can contain %
 	sPath.Replace("$NETWORK", (m_pNetwork ? m_pNetwork->GetName() : "znc"));
@@ -92,10 +86,7 @@ void CLogMod::PutLog(const CString& sLine, const CString& sWindow /*= "Status"*/
 	if (!CFile::Exists(sLogDir)) CDir::MakeDir(sLogDir);
 	if (LogFile.Open(O_WRONLY | O_APPEND | O_CREAT))
 	{
-		snprintf(buffer, sizeof(buffer), "[%02d:%02d:%02d] ",
-				timeinfo->tm_hour, timeinfo->tm_min, timeinfo->tm_sec);
-
-		LogFile.Write(buffer + sLine + "\n");
+		LogFile.Write(CUtils::FormatTime(curtime, "[%H:%M:%S] ", m_pUser->GetTimezone()) + sLine + "\n");
 	} else
 		DEBUG("Could not open log file [" << sPath << "]: " << strerror(errno));
 }
diff --git a/modules/simple_away.cpp b/modules/simple_away.cpp
index a49447fc..a55048be 100644
--- a/modules/simple_away.cpp
+++ b/modules/simple_away.cpp
@@ -189,9 +189,7 @@ private:
 			sReason = SIMPLE_AWAY_DEFAULT_REASON;
 
 		time_t iTime = time(NULL);
-		setenv("TZ", m_pUser->GetTimezone().c_str(), 1);
-		CString sTime = ctime(&iTime);
-		sTime.Trim();
+		CString sTime = CUtils::CTime(iTime, m_pUser->GetTimezone());
 		sReason.Replace("%s", sTime);
 
 		return sReason;
diff --git a/src/User.cpp b/src/User.cpp
index e03460f3..71198a9b 100644
--- a/src/User.cpp
+++ b/src/User.cpp
@@ -61,7 +61,7 @@ CUser::CUser(const CString& sUserName)
 	// set path that depends on the user name:
 	m_sUserPath = CZNC::Get().GetUserPath() + "/" + m_sUserName;
 
-	m_sTimezone = "GMT";
+	m_sTimezone = "";
 	m_fTimezoneOffset = 0;
 	m_sNick = m_sCleanUserName;
 	m_sIdent = m_sCleanUserName;
@@ -500,16 +500,7 @@ CString CUser::ExpandString(const CString& sStr) const {
 }
 
 CString& CUser::ExpandString(const CString& sStr, CString& sRet) const {
-	time_t iUserTime = time(NULL);
-	setenv("TZ", m_sTimezone.c_str(), 1);
-	char *szTime = ctime(&iUserTime);
-	CString sTime;
-
-	if (szTime) {
-		sTime = szTime;
-		// ctime() adds a trailing newline
-		sTime.Trim();
-	}
+	CString sTime = CUtils::CTime(time(NULL), m_sTimezone);
 
 	sRet = sStr;
 	sRet.Replace("%user%", GetUserName());
@@ -537,27 +528,21 @@ CString CUser::AddTimestamp(const CString& sStr) const {
 }
 
 CString& CUser::AddTimestamp(const CString& sStr, CString& sRet) const {
-	char szTimestamp[1024];
-	time_t tm;
 	sRet = sStr;
 
 	if (!GetTimestampFormat().empty() && (m_bAppendTimestamp || m_bPrependTimestamp)) {
-		time(&tm);
-		setenv("TZ", m_sTimezone.c_str(), 1);
-		size_t i = strftime(szTimestamp, sizeof(szTimestamp), GetTimestampFormat().c_str(), localtime(&tm));
-		// If strftime returns 0, an error occured in format, or result is empty
-		// In both cases just don't prepend/append anything to our string
-		if (0 == i) {
+		CString sTimestamp = CUtils::FormatTime(time(NULL), GetTimestampFormat(), m_sTimezone);
+		if (sTimestamp.empty()) {
 			return sRet;
 		}
 
 		if (m_bPrependTimestamp) {
-			sRet = szTimestamp;
+			sRet = sTimestamp;
 			sRet += " " + sStr;
 		}
 		if (m_bAppendTimestamp) {
 			sRet += " ";
-			sRet += szTimestamp;
+			sRet += sTimestamp;
 		}
 	}
 	return sRet;
diff --git a/src/Utils.cpp b/src/Utils.cpp
index 70610c9c..69aa9d86 100644
--- a/src/Utils.cpp
+++ b/src/Utils.cpp
@@ -338,6 +338,60 @@ void CUtils::PrintStatus(bool bSuccess, const CString& sMessage) {
 	fflush(stdout);
 }
 
+CString CUtils::CTime(time_t t, const CString& sTZ) {
+	char s[30] = {}; // should have at least 26 bytes
+	if (sTZ.empty()) {
+		ctime_r(&t, s);
+		// ctime() adds a trailing newline
+		return CString(s).Trim_n();
+	}
+
+	// backup old value
+	char* oldTZ = getenv("TZ");
+	if (oldTZ) oldTZ = strdup(oldTZ);
+	setenv("TZ", sTZ.c_str(), 1);
+
+	ctime_r(&t, s);
+
+	// restore old value
+	if (oldTZ) {
+		setenv("TZ", oldTZ, 1);
+		free(oldTZ);
+	} else {
+		unsetenv("TZ");
+	}
+
+	return CString(s).Trim_n();
+}
+
+CString CUtils::FormatTime(time_t t, const CString& sFormat, const CString& sTZ) {
+	char s[1024] = {};
+	tm m;
+	if (sTZ.empty()) {
+		localtime_r(&t, &m);
+		strftime(s, sizeof(s), sFormat.c_str(), &m);
+		return s;
+	}
+
+	// backup old value
+	char* oldTZ = getenv("TZ");
+	if (oldTZ) oldTZ = strdup(oldTZ);
+	setenv("TZ", sTZ.c_str(), 1);
+
+	localtime_r(&t, &m);
+	strftime(s, sizeof(s), sFormat.c_str(), &m);
+
+	// restore old value
+	if (oldTZ) {
+		setenv("TZ", oldTZ, 1);
+		free(oldTZ);
+	} else {
+		unsetenv("TZ");
+	}
+
+	return s;
+}
+
 bool CTable::AddColumn(const CString& sName) {
 	for (unsigned int a = 0; a < m_vsHeaders.size(); a++) {
 		if (m_vsHeaders[a].Equals(sName)) {