diff --git a/test/cases/db-update.bats b/test/cases/db-update.bats
index 1da7eef..6604841 100644
--- a/test/cases/db-update.bats
+++ b/test/cases/db-update.bats
@@ -92,7 +92,16 @@ load ../lib/common
 	db-update
 	checkPackage extra pkg-any-a
 
-	releasePackage extra pkg-any-a
+	# don't let __buildPackage use the cached build; we want to
+	# force a new build with a different PKGEXT.
+	if [[ -n ${BUILDDIR} ]]; then
+		mv -T "${BUILDDIR}/$(__getCheckSum "${TMP}/svn-packages-copy/pkg-any-a/trunk/PKGBUILD")"{,.bak}
+	fi
+	PKGEXT=.pkg.tar.gz releasePackage extra pkg-any-a
+	if [[ -n ${BUILDDIR} ]]; then
+		rm -rf "${BUILDDIR}/$(__getCheckSum "${TMP}/svn-packages-copy/pkg-any-a/trunk/PKGBUILD")"
+		mv -T "${BUILDDIR}/$(__getCheckSum "${TMP}/svn-packages-copy/pkg-any-a/trunk/PKGBUILD")"{.bak,}
+	fi
 	run db-update
 	[ "$status" -ne 0 ]
 }