IOS Versions and Affection Sets
MPLS is not included in all IOS images. The Adaptation 12.4 affection set images are rather complicated, as the names and agreeable depend on the accouterments platform. The accepted aphorism of deride is that you charge one of the "Advanced," "Service Provider," or "Enterprise" affection sets if you appetite to use MPLS. For example, for the 2800 alternation routers, you can run MPLS if you accept the "Advanced IP Services" version, any of the "SP Services" versions, or any of the "Enterprise Services" versions (including "Enterprise Services," "Advanced Enterprise Services," "Advanced Enterprise Services with SNA," or "Enterprise Services with Crypto" releases).
If you are unsure, amuse argue Cisco's Affection Navigator http://tools.cisco.com/ITDIT/CFN/jsp/index.jsp.