diff --git a/README.SRC b/README.SRC
index f93fd31e..cc42e6f5 100644
--- a/README.SRC
+++ b/README.SRC
@@ -75,13 +75,18 @@ Tools needed to build/modify the UPX sources
 To compile the packer sources
 -----------------------------
 
-  set the environment variable UPX_UCLDIR to point to your
-  UCL installation, e.g.
+  Set the environment variable UPX_UCLDIR to point to your
+  UCL build directory, e.g.
 
      set UPX_UCLDIR=c:\src\ucl-1.03                   (DOS / Windows)
      export UPX_UCLDIR=$HOME/local/src/ucl-1.03       (Unix)
 
-  then type
+  Set the environment variable UPX_LZMADIR to point to your
+  to your unpacked lzma443.tar.bz2 source directory, e.g.
+
+     export UPX_LZMADIR=$HOME/local/src/lzma-4.43     (Unix)
+
+  Finally type
 
      make