The mural says it was "designed in collaboration with Bus Eireann staff and painted by Isabel Donovan and Mike Greenlaw with help from Michelle and Charlotte".
I'm not sure when the mural was painted, but I found a 2006 blog entry by a fellow named Donal that mentions the mural being a recent work. The blog also includes pictures of sections of the mural that don't exist any more, so I'll include a link to it here: http://www.donal.ie/2006/09/13/cork-bus-station-mural/
About half of this piece disappeared in 2008, it seems, along with the section of wall that it was painted on. It is sad the mural has been so badly damaged....
These photos were all taken by me in October 2012.