It is quite easy for someone to use more than 5 capital letters in a message. Perhaps a better method would be to kick people who use a certain percentage of capital letters, for example: OMG JOIN #NEWBP0WNAGE NOW!!! That sentence has 20 out of 28 characters capitalised, which would be about 71% capital letters. The maximum could be set around 50%, or even better, inclue a method for the user to define the percentage.