Sms Text Time Stamp Question

I received a text msg from someone at 8am. The time stamp of the text showed 7am on my phone (not exact times). The person tells me that he had just sent it within 5 min before 8am. The person doesn't use a BB nor is he with the same carrier. I guess my question is......Is it at all possible for a person to send a text msg around 8am and when it gets to me, the time stamp of that msg shows 7am? We were within 500 ft from each other when this "supposed"to have happened. The following text from this person came in showing normal times. Thanks for the help

i think it stamps when you get the message on the bb. my 8900 was off the night before, and turned on at 8am. 2 messages indicated 8am time stamps