diff --git a/main/Makefile.am b/main/Makefile.am
index ea2d8a5e0..460bbffd6 100644
--- a/main/Makefile.am
+++ b/main/Makefile.am
@@ -4,6 +4,7 @@ EXTRA_DIST = TODO reconf spec README mime
 BUILT_SOURCES = trunk_version.h
 CLEANFILES = trunk_version.h
 
+.PHONY: trunk_version.h
 trunk_version.h:
 	@if test -d ../.svn ; then \
 		if test ../.svn -nt trunk_version.h ; then \