How Do I Get My SPRINT Phone To Send A Text To Ipod Touches?

[Hoodie]

My phone will NOT send a text to an ipod touch! It makes me so mad, all my friends who have verison phones can text them, but my SPRINT phone will not let me! why not? I want to know how to fix it, because right now my boyfriends phone is shut off & he wants to text me from there because the Facebook chat SUCKS. So, how do I make it work? When I reply to the text by hitting reply, or even type in the number from the ipod touch and text it, after I send it I get a text from some 4 digit number saying that the format is not correct. How can I make this work? Any help would be GREATLY appreciated