--- a/www-client/firefox/firefox-33.0.ebuild	2014-10-14 15:17:47.000000000 -0300
+++ b/www-client/firefox/firefox-33.0.ebuild	2014-10-15 16:22:57.690644198 -0300
@@ -176,6 +176,9 @@
 	# Don't error out when there's no files to be removed:
 	sed 's@\(xargs rm\)$@\1 -f@' \
 		-i "${S}"/toolkit/mozapps/installer/packager.mk || die
+	
+	# Ensure configure is actually compatible with sh shells
+	sed -i 's/if test \(.*\) == /if test \1 = /' "${S}"/memory/jemalloc/src/configure
 
 	eautoreconf