1. A method for caching a dynamically generated object identified as not cacheable, the method comprising the steps of: receiving, by an intermediary device located between a plurality of clients and an originating server, from the originating server, a dynamically generated object identified as not cacheable generated in response to a first request from a first client of the plurality of clients; transmitting, by the intermediary device, the dynamically generated object to the first client, responsive to the first request; retaining, in a cache on the intermediary device, the dynamically generated object identified as not cacheable after transmitting the dynamically generated object to the first client; receiving, by the intermediary device, a second request from a second client of the plurality of clients for the dynamically generated object responding, by the intermediary device, to the second request with the cached dynamically generated object identified as not cacheable generated in response to the first request; receiving, by the intermediary device, a request to invalidate the cached dynamically generated object identified as not cacheable; and marking, by the intermediary device in response to the request to invalidate the cached dynamically generated object identified as not cacheable, the cached dynamically generated object identified as not cacheable as invalid.