diff --git a/Doc/Makefile b/Doc/Makefile
index 0c5b7e1..fedd570 100644
--- a/Doc/Makefile
+++ b/Doc/Makefile
@@ -76,7 +76,7 @@
 
 # Ideally, you shouldn't need to edit beyond this point
 
-RELEASE=1.5.1p1
+RELEASE=1.5.2a1
 VERSION=1.5
 
 MANDVIFILES=	api.dvi ext.dvi lib.dvi ref.dvi tut.dvi