libc does not have an el_CY locale. This is for Greek in the Republic of Cyprus. The locale is mostly a copy from el_GR with differences in currency (pound instead of euro), address format and maybe more. If you need any more information about the locale let me know. en_CY and tr_CY are also necessary to provide coverage for all official languages in the Republic of Cyprus. If you care to add those too I'd be happy to help you.
Please provide locale files implementing your proposed locales. I recommend having a look at <URL: http://www.student.uit.no/~pere/linux/glibc/ > to learn how to write locales.
*** This bug has been marked as a duplicate of 531 ***