diff --git a/Contrib/NSISdl/httpget.cpp b/Contrib/NSISdl/httpget.cpp
index 9a888500..fb18e881 100644
--- a/Contrib/NSISdl/httpget.cpp
+++ b/Contrib/NSISdl/httpget.cpp
@@ -481,3 +481,17 @@ int JNL_HTTPGet::peek_bytes(char *buf, int len)
   if (m_con && m_http_state==3) return m_con->peek_bytes(buf,len);
   return 0;
 }
+
+__int64 JNL_HTTPGet::content_length()
+{
+  char *p=getheader("content-length:");
+  if (!p) return 0;
+  __int64 cl = myatoi64(p);
+  if (cl > 0) return cl;
+
+  // workaround for bug #1744091
+  // some buggy apache servers return negative values for sizes
+  // over 2gb - fix it for them
+  if (cl < 0)
+    return __int64(unsigned(cl));
+}
diff --git a/Contrib/NSISdl/httpget.h b/Contrib/NSISdl/httpget.h
index c8b2c76a..c87e1811 100644
--- a/Contrib/NSISdl/httpget.h
+++ b/Contrib/NSISdl/httpget.h
@@ -43,7 +43,6 @@
 #define _HTTPGET_H_
 
 #include "connection.h"
-#include "util.h"
 
 class JNL_HTTPGet
 {
@@ -71,7 +70,7 @@ class JNL_HTTPGet
     int get_bytes(char *buf, int len);
     int peek_bytes(char *buf, int len);
 
-    __int64 content_length() { char *p=getheader("content-length:"); if (p) return myatoi64(p); return 0; }
+    __int64 content_length();
 
     JNL_Connection *get_con() { return m_con; }