Some software packages at Wikipedia here

At CASC (Center for Applied Scientific Computing) there is ODEPACK (Serial FORTRAN solvers for Ordinary Differential Equation initial value problems) here and BABEL:

"Babel provides high-performance language interoperability and middleware for scientific applications. It also provides coarse-grained distributed computing using remote method invocation. Babel currently supports C, C++, Java, Python, and various dialects of Fortran."

Also, you can try SUNDIALS (SUite of Nonlinear and DIfferential/ALgebraic equation Solvers) available here.

SUNDIALS provides a **Matlab** interface to CVODES (solves IVP for ODE systems), IDA (solves IVP dor DAE systems) and KINSOL (solves nonlinear algebraic problems).