[c-nsp] mpls mtu of 1492

[tusker keg]

howdy folks

I have a test platform of routers connected  to  Cisco 2950T switches.
 I am testing mpls and mpls based vpns but unfortunately I have ran
into problems. The 2950T do not support baby giants (frames)

http://www.cisco.com/en/US/products/hw/switches/ps700/products_configuration_example09186a008010edab.shtml#subtopic1G

What will be the effect of setting the mpls mtu to a value lower than 1500.