As far as I know it's not frowned upon. Tibetans have names that, in general, are holy names, or the meaning is something holy. For example, Ngawang is another name for Manjushri, suposedly the bodhisattva of wisdom.
But if you want a confirmation, contact www.dharmawheel.net
, the sister site of this forum, that focuses on other traditions than Theravada, namely, Tibetan buddhism.