Mobile agents are no longer a theoretical issue since different architectures for their realization have been proposed. With the increasing market of electronic commerce it becomes an interesting aspect to use autonomous mobile agents Sor electronic business transactions. Being involved in money transactions, supplementary security features Sar mobile agent systems have to be ensured. fn this paper Mle present an architecture for a mobile agent system which guarantees security Sor the host as well as security for the agent. This architecture additionally offers fault tolerance for the whole agent sq stem at a high level. To handle these issues for mobile agents Mie use various encryption mechanisms and we apply a novel method for mobile agent systems bg using distributed transactions processing based on the OMG Object Transaction Service in our architecture, With this security architecture an agent will be enabled to do money transactions.