It's true. I went to block this number from my phone on my Block list on Sprint. It does not allow for any number that is more than 10 digits. But, because of your post saying that Spring took care of it for you, I decided to call and give it a try.
Sure enough they can block 11-digit numbers. They said it takes 24-48 hours to complete, but they can do it! What a nice surprise. Thank you so much for posting this! I appreciate it!
called 12/22/13 6:30pm . I was on another call when this one came in and in the process lost 1st call and got the 'unavailable' and lost it trying to get my first call back. This showed as an 11digit number without spaces. I was able to add the 'number', if that is what it is, to my reject list. Only time will tell if that is in fact the number they were calling from.