I just received this by e-mail:
Can anyone fluent in Klingon translate what this Klingon Santa is saying?
"May y'all enjoy Christmas and may y'all enjoy the new year."
QISmaS = Not a canonical tlhIngan Hol word, but a phonetic approximation of "Christmas".
bo- = Pronomial prefix; indicates that the subject of the verb is second-person plural and the object is third-person. "Y'all do something to him/her/it/them"
'ej = and (joining sentences)
DIS = year
chu' = be new
Edit: Also, the pIqaD text on his sleigh appears to say Sannta. That consonant cluster in the middle isn't really allowed in traditional tlhIngan Hol, but I think the Empire will forgive the artist; after all, it is QISmaS ;)
Indeed, big kudos to the artist for doing their research; most people take a lot of shortcuts when writing "Klingon", and that's quite understandable, but whenever somebody does get it right, it's a real treat for those of us in the Klingon-speaking community :)
According to omniglot.com it means:
Merry Christmas and Happy New Year!