The value of the deal was not disclosed.
PicNet, which has provided IT infrastructure and network support and software development, now provided project management and consulting under the new deal.
PicNet managing director Marco Tapia said the integrator had to be "very flexible and add more value" to win the deal.
"Because of the [financial crisis] we had to renegotiate the contract," he said.
It extended the relationship established in 2003.
Projects included disaster recovery, network consolidation and winde-area network optimisation.
Glenn Casarotto, IT Manager at DMS Maritime, said the "partnership allowed the reseller to benefit from technology without having to be IT experts ourselves".
"What working with PicNet has allowed us to do is focus on our own skills and competencies," Casarotto said.