diff --git a/dtool/Config.Linux.pp b/dtool/Config.Linux.pp
index 41d4f75870..80cf1d01bf 100644
--- a/dtool/Config.Linux.pp
+++ b/dtool/Config.Linux.pp
@@ -139,3 +139,8 @@
 // What is the syntax of the STL allocator declaration?  See
 // LocalSetup.pp for allowable values.
 #define STL_ALLOCATOR GNU
+
+// The dynamic library file extension (usually .so .dll or .dylib):
+#define DYNAMIC_LIB_EXT .so
+  
+
diff --git a/dtool/Config.Win32.pp b/dtool/Config.Win32.pp
index 6f14961077..fc0406470c 100644
--- a/dtool/Config.Win32.pp
+++ b/dtool/Config.Win32.pp
@@ -135,3 +135,8 @@
 
 // can Intel C++ build this directory successfully (if not, change CC to msvc)
 #define NOT_INTEL_BUILDABLE false
+
+// The dynamic library file extension (usually .so .dll or .dylib):
+#define DYNAMIC_LIB_EXT .dll
+  
+
diff --git a/dtool/pptempl/Template.unix.pp b/dtool/pptempl/Template.unix.pp
index 41fdea9532..c85b5785af 100644
--- a/dtool/pptempl/Template.unix.pp
+++ b/dtool/pptempl/Template.unix.pp
@@ -40,7 +40,7 @@
   // $[bin_targets] the list of binaries.  $[test_bin_targets] is the
   // list of binaries that are to be built only when specifically asked
   // for.
-  #define lib_targets $[active_target(metalib_target lib_target ss_lib_target noinst_lib_target):%=$[ODIR]/lib%.so]
+  #define lib_targets $[active_target(metalib_target lib_target ss_lib_target noinst_lib_target):%=$[ODIR]/lib%$[DYNAMIC_LIB_EXT]]
 
   #define static_lib_targets $[active_target(static_lib_target):%=$[ODIR]/lib%.a]
   #define bin_targets $[active_target(bin_target noinst_bin_target sed_bin_target):%=$[ODIR]/%]
@@ -330,7 +330,7 @@ igate : $[get_igatedb(metalib_target lib_target ss_lib_target)]
 
   #define varname $[subst -,_,lib$[TARGET]_so]
 $[varname] = $[sources]
-  #define target $[ODIR]/lib$[TARGET].so
+  #define target $[ODIR]/lib$[TARGET]$[DYNAMIC_LIB_EXT]
   #define sources $($[varname])
 
 $[target] : $[sources] $[static_lib_dependencies]
@@ -345,7 +345,7 @@ $[TAB] $[SHARED_LIB_C]
 // Here are the rules to install and uninstall the library and
 // everything that goes along with it.
 #define installed_files \
-    $[install_lib_dir]/lib$[TARGET].so \
+    $[install_lib_dir]/lib$[TARGET]$[DYNAMIC_LIB_EXT] \
     $[INSTALL_SCRIPTS:%=$[install_bin_dir]/%] \
     $[INSTALL_HEADERS:%=$[install_headers_dir]/%] \
     $[INSTALL_DATA:%=$[install_data_dir]/%] \
@@ -359,8 +359,8 @@ uninstall-lib$[TARGET] :
 $[TAB] rm -f $[sort $[installed_files]]
 #endif
 
-$[install_lib_dir]/lib$[TARGET].so : $[ODIR]/lib$[TARGET].so
-#define local $[ODIR]/lib$[TARGET].so
+$[install_lib_dir]/lib$[TARGET]$[DYNAMIC_LIB_EXT] : $[ODIR]/lib$[TARGET]$[DYNAMIC_LIB_EXT]
+#define local $[ODIR]/lib$[TARGET]$[DYNAMIC_LIB_EXT]
 #define dest $[install_lib_dir]
 $[TAB] $[INSTALL]
 
@@ -426,7 +426,7 @@ $[TAB] $[INTERROGATE_MODULE] -oc $[target] -module "$[igatemod]" -library "$[iga
 #forscopes noinst_lib_target
 #define varname $[subst -,_,lib$[TARGET]_so]
 $[varname] = $[patsubst %,$[%_obj],$[compile_sources]]
-#define target $[ODIR]/lib$[TARGET].so
+#define target $[ODIR]/lib$[TARGET]$[DYNAMIC_LIB_EXT]
 #define sources $($[varname])
 $[target] : $[sources] $[static_lib_dependencies]
 #if $[filter %.cxx %.yxx %.lxx,$[get_sources]]