With all the different agent frameworks being built by different entities and with different goals in mind it was no surprise that they were not interoperabile. As a starting point, the The Foundation for Intelligent Physical Agents (FIPA) developed a set of specifications that would allow heterogeneous agents to interoperate. While these specifications are far from perfect and failed to achieve widespread support in the agent world, they are closer to a standard than anything else is.
On 8 June 2005, after years of inactivity and decline, FIPA was officially accepted by the IEEE as its eleventh standards committee, and will be known as the FIPA Standards Committee. It has also changed its original goal to moving standards for agents and agent-based systems into the wider context of software development in general. So probably the FIPA approach was not wrong, but ahead of its time, and with the benefits provided by the umbrella of a large standards organization like IEEE, FIPA will be reborn.
More info: http://www.fipa.org/about/fipa_and_ieee.html