diff --git a/src/log4cpp.cpp b/src/log4cpp.cpp
index 9581282..403fe86 100644
--- a/src/log4cpp.cpp
+++ b/src/log4cpp.cpp
@@ -17,7 +17,6 @@
 #include <cstdarg>
 #include <cstdlib>
 #include <ctime>
-#include <cmath>
 #include <iomanip>
 #include <iostream>
 #include <sstream>
@@ -35,13 +34,12 @@ void print_timestamp()
 	// retrieve accurate time for milliseconds display
 	struct timeval secs;
 	(void)::gettimeofday(&secs, nullptr);
-	int ms = static_cast<int>(std::roundf(secs.tv_usec / 1000.0)) % 1000;
 
 	// create a date/time stamp
 	char dtstamp[20];
 	std::strftime(dtstamp, 20, "%F %T", std::localtime(&secs.tv_sec));
 
-	std::cerr << dtstamp << "." << std::setw(3) << ms << " ";
+	std::cerr << dtstamp << "." << std::setw(6) << secs.tv_usec << " ";
 #if __APPLE__
 	std::cerr << getprogname() << "[" << getpid() << "] ";
 #elif __linux__