diff --git a/install-all.sh b/install-all.sh
index 9b145d4b..10e090da 100755
--- a/install-all.sh
+++ b/install-all.sh
@@ -10,6 +10,8 @@ for package in $PACKAGES
 do
     echo Installing $package
     cd $package
-    $CABAL configure --enable-tests && $CABAL build && $CABAL test && ./Setup.lhs install || exit 1
+    ($CABAL configure --enable-tests ||
+        ($CABAL install --only-dependencies --enable-tests && $CABAL configure --enable-tests)
+    ) && $CABAL build && $CABAL test && ./Setup.lhs install || exit 1
     cd ..
 done