May 7, 2014 in answer
I solved this issue myself. It seems the original ICU library just didn’t contain the needed transliterators. I added REMI repository (http://rpms.famillecollet.com/enterprise/6/remi/mirror) and installed libicu-last and libicu-last-devel from this repo (via yum). Then I recompiled the extension using
pecl install -f intl-3.0.0.