I am not sure how phones interpret these things, but when I send a
or :( to someone that ISN'T on BBOS 5, they get the text version of what I sent. Also, when, for example, my girlfriend sends me one of those many faces from her LG enV Touch, it comes through with a mess of characters.
So, firstly, I don't know. Secondly, people on the other end are probably getting the txt version anyway.