MNCC further reading

Hello. Could you advice me where to read more about MNCC protocol? openbsc/openbsc/include/openbsc/mncc.h references ETSI TS 100 940 which indeed has a lot of variables like MNCC.RECALL.IND in call control diagrams - but where are the reference to actual protocol? I've tried to google but got tons of unrelated junk :( Pardon if I'm asking smth obvious or already documented. Is there some library which will let me easily create simple tool which speaks mncc with openbsc (libmsc)? -- best regards, Max, http://fairwaves.ru