The cross section of the process $e^+e^-to pi^+pi^-pi^0$ was measured in the Spherical Neutral Detector (SND) experiment at the VEPP-2M collider in the energy region $sqrt[]{s}$ below 980 MeV. This measurement was based on about $1.2 times 10^6$ selected events. The obtained cross section was analyzed together with the SND and DM2 data in the energy region $sqrt[]{s}$ up to 2 GeV. The $omega$-meson parameters: $m_omega=782.79pm 0.08pm 0.09$ MeV, $Gamma_omega=8.68pm 0.04pm 0.15$ MeV and $sigma(omegato 3pi)=1615pm 9pm 57$ nb were obtained. It was found that the experimental data cannot be described by a sum of only $omega$, $phi$, $omega^prime$ and $omega^{primeprime}$ resonances contributions. This can be interpreted as a manifestation of $rhoto 3pi$ decay, suppressed by $G$-parity, with relative probability $B(rhoto 3pi) = (1.01pm^{0.54}_{0.36}pm 0.034) times 10^{-4}$.
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