diff --git a/pkgs/build-support/buildenv/builder.pl b/pkgs/build-support/buildenv/builder.pl
index c505473ee722..f6cfe52dc318 100755
--- a/pkgs/build-support/buildenv/builder.pl
+++ b/pkgs/build-support/buildenv/builder.pl
@@ -169,7 +169,7 @@ while (scalar(keys %postponed) > 0) {
     my @pkgDirs = keys %postponed;
     %postponed = ();
     foreach my $pkgDir (sort @pkgDirs) {
-        addPkg($pkgDir, 2, $priorityCounter++);
+        addPkg($pkgDir, 2, $ENV{"checkCollisionContents"} eq "1", $priorityCounter++);
     }
 }