Greece wants a solution to its crippling debt that applies to all its sovereign bonds expiring up to 2035, a government source said on Monday, adding that the process should remain voluntary and any deal must include the European Central Bank. This would be a marked expansion from a previous, now defunct, plan agreed by the EU in July, under which Greece's debt burden would be lowered through a bond exchange involving paper maturing up to 2020. "We are looking at the entire Greek debt, expiring through to 2035... It does not stop at 2020 as the previous model did,"...