Magnetic field orientation (in the plane of the sky) for 17 individual masers with P_l< 5% (red segment) and strength for four (non-saturated) masers for which the Zeeman splitting was measured. The 8.4 GHz emission imaged with the VLA (beamsize ~ 0.′′2) by Wilner et al. (1999) (yellow contours: corresponding to 0.02, 0.06, 0.1, 0.2, 0.3 mJy beam^-1) is overplotted onto the 1.4 mm continuum emission mapped with the PdBI (beamsize ~ 0.′′5) by Wyrowski et al. (1999) (gray scale and black contours: same as in Fig. 1). The radio continuum shows a main central component, the synchrotron jet, and two (western and eastern) secondary components (see Sect. 4.1 for an interpretation).