diff --git a/indra/cmake/JsonCpp.cmake b/indra/cmake/JsonCpp.cmake
index 952af655b1..7e2becc06f 100755
--- a/indra/cmake/JsonCpp.cmake
+++ b/indra/cmake/JsonCpp.cmake
@@ -10,9 +10,15 @@ if (USESYSTEMLIBS)
 else (USESYSTEMLIBS)
   use_prebuilt_binary(jsoncpp)
   if (WINDOWS)
-    set(JSONCPP_LIBRARIES 
-      debug json_libmtd.lib
-      optimized json_libmt.lib)
+    if (ND_BUILD64BIT_ARCH)
+      set(JSONCPP_LIBRARIES
+        debug json_libmtd.lib
+        optimized json_libmt.lib)
+    else (ND_BUILD64BIT_ARCH)
+      set(JSONCPP_LIBRARIES
+        debug json_libmdd.lib
+        optimized json_libmd.lib)
+    endif (ND_BUILD64BIT_ARCH)
   elseif (DARWIN)
     set(JSONCPP_LIBRARIES libjson_darwin_libmt.a)
   elseif (LINUX)