Yes u can !
But...
for commercial use you have to buy a licence.
Commercial use is defined as: Making the services that the TeamSpeak Server provides available as a product, or part of a product you sell to 3rd parties. In other words: If you ask money from 3rd parties for the use of Your TeamSpeak Server, either directly or indirectly (when you provide the TeamSpeak Server as part of a product (for free or not)). You have to use the commercial version of the TeamSpeak server and are not allowed to use this public version.
more about
:
http://www.teamspeak.net/modules.php...iew&file=index