A thread on Reddit has details on new regional restrictions Valve is apparently imposing on games gifted through Steam (thanks VG247). This is another attempt to control the ability to buy games cheaply on the service by taking advantage of regional pricing differences, and this post shows an example of the type of message this policy produces:

This is a restricted gift which can only be redeemed in these countries: Indonesia, Malaysia, Philippines, Singapore, Thailand

In addition, if you decide to redeem this restricted gift, you can only play it within the countries listed above.

Note that using an IP proxy or other methods to disguise the place of your residence to activate this gift is a violation of the Steam Subscriber Agreement and may result in restrictions on this Steam account.