On exiting the country through Ho Chi Minh City airport, carry-on bags and checked luggage are usually X - rayed by customs prior to immigration and airport security. Customs Office will notice any DVDs. It is illegal to export more than 5 DVDs! You may be asked to pay a fine of between 500,000 VND and 1,000,000 VND!  Customs will try to convince persons to pay the fine and keep the DVDs. Sounds like a scam. If you are asked to pay any money (fine) ask for a receipt. At least then you know you ARE paying a fine rather than lining somebody's pocket. Also if you buy DVDs from department stores don't assume they are 100% legal either.

They may now be trying to stop all DVDs from being exported or let out with a fine. Be warned about this situation.

A reatail DVD is not worth more than 100.000 VND with a color jewel box (on the street they give you a plastic bag, the box costs more than the DVD itself...), so if the are asking for money just leave the DVD and better AVOID buying any expensive DVD.
With new movies it is obvious that if the DVD is not already sold on Amazon.com you will get a very bad copy made with a videocam in a movie theather or best case a copy of an asian DVD with Korean or Russian subtitles.