We report on XMM-Newton observations of two X–ray transient millisecond pulsars ( XRTMSPs ) .
We detected XTE J0929–314 with an unabsorbed luminosity of \sim 7 \times 10 ^ { 31 } erg s ^ { -1 } ( 0.5–10 keV ) at a fiducial distance of 10 kpc .
The quiescent spectrum is consistent with a simple power law spectrum .
The upper limit on the flux from a cooling neutron star atmosphere is about 20 \% of the total flux .
XTE J1807–294 instead was not detected .
We can put an upper limit on the source quiescent 0.5–10 keV unabsorbed luminosity \lower 2.15 pt \hbox { $ \buildrel < \over { \sim } $ } 4 \times 10 ^ { 31 } erg s ^ { -1 } at 8 kpc .
These observations strenghten the idea that XRTMSPs have quiescent luminosities significantly lower than classical neutron star transients .