-PKG_CHECK_MODULES(SYNFIG, synfig ETL sigc++-2.0,,[
- AC_MSG_ERROR([ ** Unable to set up dependent libraries])
+PKG_CHECK_MODULES(SYNFIG, [synfig >= 0.61.06] [ETL >= 0.04.09] sigc++-2.0,,[
+ AC_MSG_ERROR([ ** Unable to set up dependent libraries (synfig >= 0.61.06, ETL >= 0.04.09)])