Multi-core systems are now the norm, and reconfigurable systems have shown substantial benefits over general purpose ones. This paper presents a combination of the two: a fully featured reconfigurable multi-core processor based on the Leon3 processor. The platform has important features like cache coherency, a fully running modern OS (GNU/Linux) and each core has a tightly coupled reconfigurable coprocessor unit attached. This allows the SPARC instruction set to be extended for the running application. The multi-core reconfigurable processor architecture, including the coprocessor interface, the ICAP controller and the Linux kernel driver, is presented. The experimental results show the characteristics of the platform including: area costs, the memory contention, the reprogramming cost... Speedups up to 100x are demonstrated on a cryptography test.