Many reasons have been given for rejecting SMS style messages, but in the end I think there is one basic reason:

SMS is disrespectful.
If somebody is asking for help, it is simply good manners to ask in a respectful way. Use of SMS in a question is simply lazy and suggests that the questioner's time is somehow more valuable than that of those being asked. The same goes for any question in which far too little infomation is given or which suggests that the questioner has made little effort to find an answer by his own efforts.

With this in mind, I think that Per Guldmann's suggestion is the best, that is: closing (but don't delete) post and inviting the poster to make a new post in plain english.