diff --git a/src/mongo/util/time_support.cpp b/src/mongo/util/time_support.cpp
index 01101ae..2167f1b 100644
--- a/src/mongo/util/time_support.cpp
+++ b/src/mongo/util/time_support.cpp
@@ -541,6 +541,42 @@ namespace {
 
 }  // namespace
 
+#if defined(sun) || defined(__sun)
+static int leapyear (int year)
+{
+    return ((year % 4) == 0 && ((year % 100) != 0 || (year % 400) == 0));
+}
+
+/*
+ * This is a simple implementation of timegm() which does what is needed
+ * by create_output() -- just turns the "struct tm" into a GMT time_t.
+ * It does not normalize any of the fields of the "struct tm", nor does
+ * it set tm_wday or tm_yday.
+ */
+time_t timegm (struct tm *tm)
+{
+    int monthlen[2][12] = {
+        { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 },
+        { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 },
+    };
+    int year, month, days;
+
+    days = 365 * (tm->tm_year - 70);
+    for (year = 70; year < tm->tm_year; year++) {
+        if (leapyear(1900 + year)) {
+            days++;
+        }
+    }
+
+    for (month = 0; month < tm->tm_mon; month++) {
+        days += monthlen[leapyear(1900 + year)][month];
+    }
+    days += tm->tm_mday - 1;
+
+    return ((((days * 24) + tm->tm_hour) * 60 + tm->tm_min) * 60 + tm->tm_sec);
+}
+#endif
+
     StatusWith<Date_t> dateFromISOString(const StringData& dateString) {
         std::tm theTime;
         int millis = 0;