diff --git a/configure.ac b/configure.ac
index 0266b96..1a991da 100644
--- a/configure.ac
+++ b/configure.ac
@@ -26,7 +26,7 @@ if test "$build" != "$host" -a "${PKG_CONFIG_LIBDIR}" = ""; then
 fi
 
 CACA="no"
-PKG_CHECK_MODULES(caca, caca >= 0.99.beta9,
+PKG_CHECK_MODULES(CACA, caca >= 0.99.beta9,
  [CACA="yes"],
  [AC_MSG_RESULT(no)
   AC_MSG_ERROR([you need libcaca version 0.99.beta9 or later])])
diff --git a/src/Makefile.am b/src/Makefile.am
index d3053b3..b521a18 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -8,6 +8,6 @@ ttyvaders_SOURCES = \
 	ttyvaders.c \
 	ground.c \
 	$(NULL)
-ttyvaders_CFLAGS = `pkg-config --cflags caca`
-ttyvaders_LDFLAGS = `pkg-config --libs caca` -lm
+ttyvaders_CFLAGS = @CACA_CFLAGS@
+ttyvaders_LDFLAGS = @CACA_LIBS@ -lm