--- src/modules/filters/Makefile.am.old	2009-07-02 21:30:28.246669953 +0200
+++ src/modules/filters/Makefile.am.old	2009-07-02 21:30:42.598920342 +0200
@@ -18,7 +18,7 @@ testfilter_la_LIBADD  = $(top_builddir)/
 
 bumpmap_la_SOURCES    = filter_bumpmap.c
 bumpmap_la_LDFLAGS    = -module -avoid-version
-bumpmap_la_LIBADD     = $(top_builddir)/src/lib/libImlib2.la
+bumpmap_la_LIBADD     = $(top_builddir)/src/lib/libImlib2.la -lm
 
 colormod_la_SOURCES   = filter_colormod.c
 colormod_la_LDFLAGS   = -module -avoid-version