Wrong text message stream when new Text

OK did the search see anyone else having the issue.

1) have multiple person you are currently texting in about same time
2) turn screen off on the iphone or let goto sleep
3) get text message from person (a)
4) unlock/open iphone which brings you to a text stream
5) current text screen will be for person (b) not for person (a)

This is even though you just received a text message from person (a) and person (b) hasn't sent for a new text message.

Problem is one makes the assumption that when open up the phone from a text messsage for person (a), you are taken to his text stream, not person (b). So many a time I end up writing something to person (b) which was meant for person (a). I don't believe my phone did this always just after a certain update it did.

ATT iphone 4.0 4.3.3 (8J2)

 

Not sure if whould have put this in a code bug iphone problem

 

so no one has any ideas?