  Characteristic properties of pionium $A_{2\pi}$ and associated low energy
s--wave cross sections $\sigma(\pi^0\pi^0\to \pi^0\pi^0)$,
$\sigma(\pi^+\pi^-\to\pi^0\pi^0)$ and $\sigma(\pi^0\pi^0\to \pi^+\pi^-)$ are
investigated with a coupled channels potential model. Some experimental results
and conclusions are to be reconsidered.
