diff --git a/Makefile b/Makefile
index 4a7001c88..eaa210d07 100644
--- a/Makefile
+++ b/Makefile
@@ -15,7 +15,7 @@
 VER_VERSION=0.9.18
 VER_DATE=`date +"%Y-%m-%d"`
 
-MAGIC_API_VERSION=0x00000001
+include magic/Makefile-apiversion
 
 
 # Where to install things:
diff --git a/magic/Makefile b/magic/Makefile
index 714584888..6d381aa3e 100644
--- a/magic/Makefile
+++ b/magic/Makefile
@@ -5,6 +5,8 @@
 # part of Tux Paint base, so "install-plugin-dev" probably hasn't
 # been run yet; hence "-I../src/" to find 'tp_magic_api.h')
 
+include Makefile-apiversion
+
 SO_TYPE=so
 
 TP_MAGIC_CFLAGS=$(shell sdl-config --cflags) \
diff --git a/magic/Makefile-apiversion b/magic/Makefile-apiversion
new file mode 100644
index 000000000..22634164e
--- /dev/null
+++ b/magic/Makefile-apiversion
@@ -0,0 +1 @@
+MAGIC_API_VERSION=0x00000001
diff --git a/magic/src/rainbow.c b/magic/src/rainbow.c
index 8e34e4026..10071f656 100644
--- a/magic/src/rainbow.c
+++ b/magic/src/rainbow.c
@@ -88,8 +88,9 @@ char * rainbow_get_description(magic_api * api, int which)
 
 // Do the effect:
 
-void do_example(void * ptr, int which, SDL_Surface * canvas, SDL_Surface * last,
-                int x, int y)
+void rainbow_linecb(void * ptr, int which,
+		    SDL_Surface * canvas, SDL_Surface * last,
+                    int x, int y)
 {
   magic_api * api = (magic_api *) ptr;
   int xx, yy;
@@ -116,7 +117,7 @@ void rainbow_drag(magic_api * api, int which, SDL_Surface * canvas,
 			   rainbow_hexes[rainbow_color][1],
 			   rainbow_hexes[rainbow_color][2]);
 
-  api->line(which, canvas, last, ox, oy, x, y, 1, do_example);
+  api->line(which, canvas, last, ox, oy, x, y, 1, rainbow_linecb);
 
   api->playsound(rainbow_snd, (x * 255) / canvas->w, 255);
 }