diff --git a/legacy/embryo/debian/rules b/legacy/embryo/debian/rules
index c8e5941132..9f7a341ab2 100755
--- a/legacy/embryo/debian/rules
+++ b/legacy/embryo/debian/rules
@@ -7,7 +7,7 @@ DEB_DH_STRIP_ARGS := --dbg-package=libembryo-dbg
 DEB_CONFIGURE_EXTRA_FLAGS := --disable-rpath --enable-doc
 DEB_CONFIGURE_SCRIPT := ./autogen.sh
 DEB_MAKE_CLEAN_TARGET := distclean
-DEB_SOURCE_VERSION := $(shell grep AC_INIT $(DEB_SRCDIR)/configure.ac|sed -e 's/AC_INIT(\[embryo\],\ \[\(.*\)\],\ \[.*@.*\])/\1/g')
+DEB_SOURCE_VERSION := $(shell grep AC_INIT $(DEB_SRCDIR)/configure.ac|sed -e 's/AC_INIT(embryo,\ \(.*\),\ .*@.*)/\1/g')
 CFLAGS += -fvisibility=hidden
 
 build/libembryo-doc::