I personally don't think it's ok to interact with an Ex unless it's to send condolences for loosing a family member or to talk about kids if you have any.

[alleykatt]

Here's reasons when it's ok and not ok to text ex bf or gf just in case some of you forgot......
http://www.thedatereport.com/dating/advice/1118-ex-etiquette-when-it-is-and-isn-t-ok-to-contact/